Olivier Guyon

Interests

No activities entered.

Courses

Scholarly Contributions

Chapters

• Guyon, O. (2018). Imaging with Adaptive Optics and Coronographs for Exoplanet Research. In Handbook of Exoplanets(p. 112).

Journals/Publications

• , G. S., , F. M., , P. B., , O. G., , T. M., & , C. C. (2021). Lyot-based Ultra-Fine Pointing Control System for Phase Mask Coronagraphs.
  More info

  High performance coronagraphic imaging at small inner working angle requiresefficient control of low order aberrations. The absence of accurate pointingcontrol at small separation not only degrades coronagraph starlight rejectionbut also increases the risk of confusing planet's photons with starlightleaking next to the coronagraph focal plane mask center. Addressing this issueis essential for preventing coronagraphic leaks, and we have thus developed anew concept, the Lyot-based pointing control system (LPCS), to control pointingerrors and other low order aberrations within a coronagraph. The LPCS usesresidual starlight reflected by the Lyot stop at the pupil plane. Oursimulation has demonstrated pointing errors measurement accuracy between 2-12nm for tip-tilt at 1.6 micron with a four quadrant phase mask coronagraph.[Journal_ref: ]
• , J. M., , O. G., , J. L., , N. J., & , J. R. (2021). Phase-induced amplitude apodization complex mask coronagraph tolerancing and analysis.
  More info

  Phase-Induced Amplitude Apodization Complex Mask Coronagraphs (PIAACMC) offerhigh-contrast performance at a small inner-working angle ($\approx$ 1$\lambda$/D) with high planet throughput ($>$ 70%). The complex mask is amulti-zone, phase-shifting mask comprised of tiled hexagons which vary indepth. Complex masks can be difficult to fabricate as there are manymicron-scale hexagonal zones ($>$ 500 on average) with continuous depthsranging over a few microns. Ensuring the broadband PIAACMC design performancecarries through to fabricated devices requires that these complex masks aremanufactured to within well-defined tolerances. We report on a simulatedtolerance analysis of a "toy" PIAACMC design which characterizes the effect ofcommon microfabrication errors on on-axis contrast performance using a simpleMonte Carlo method. Moreover, the tolerance analysis provides crucialinformation for choosing a fabrication process which yields working deviceswhile potentially reducing process complexity. The common fabrication errorsinvestigated are zone depth discretization, zone depth errors, and edgeartifacts between zones.[Journal_ref: ]
• , J. R., & , O. G. (2021). Ground-based adaptive optics coronagraphic performance under closed-loop predictive control.
  More info

  The discovery of the exoplanet Proxima b highlights the potential for thecoming generation of giant segmented mirror telescopes (GSMTs) to characterizeterrestrial --- potentially habitable --- planets orbiting nearby stars withdirect imaging. This will require continued development and implementation ofoptimized adaptive optics systems feeding coronagraphs on the GSMTs. Suchdevelopment should proceed with an understanding of the fundamental limitsimposed by atmospheric turbulence. Here we seek to address this question with asemi-analytic framework for calculating the post-coronagraph contrast in aclosed-loop AO system. We do this starting with the temporal power spectra ofthe Fourier basis calculated assuming frozen flow turbulence, and then applyclosed-loop transfer functions. We include the benefits of a simple predictivecontroller, which we show could provide over a factor of 1400 gain in raw PSFcontrast at 1 $\lambda/D$ on bright stars, and more than a factor of 30 gain onan I = 7.5 mag star such as Proxima. More sophisticated predictive control canbe expected to improve this even further. Assuming a photon noise limitedobserving technique such as High Dispersion Coronagraphy, these gains in rawcontrast will decrease integration times by the same large factors. Predictivecontrol of atmospheric turbulence should therefore be seen as one of the keytechnologies which will enable ground-based telescopes to characterizeterrrestrial planets.[Journal_ref: ]
• , K. M., , O. G., & , J. R. (2021). Spatial Linear Dark Field Control: Stabilizing Deep Contrast for Exoplanet Imaging Using Bright Speckles.
  More info

  Direct imaging of exoplanets requires establishing and maintaining a highcontrast dark field (DF) within the science image to a high degree of precision(10^-10). Current approaches aimed at establishing the DF, such as electricfield conjugation (EFC), have been demonstrated in the lab and have provencapable of high contrast DF generation. The same approaches have beenconsidered for the maintenance of the DF as well. However, these methods relyon phase diversity measurements which require field modulation; this interruptsthe DF and consequently competes with the science acquisition. In this paper,we introduce and demonstrate spatial linear dark field control (LDFC) as analternative technique by which the high contrast DF can be maintained withoutmodulation. Once the DF has been established by conventional EFC, spatial LDFClocks the high contrast state of the DF by operating a closed-loop around thelinear response of the bright field (BF) to wavefront variations that modifyboth the BF and the DF. We describe here the fundamental operating principlesof spatial LDFC and provide numerical simulations of its operation as a DFstabilization technique that is capable of wavefront correction within the DFwithout interrupting science acquisition.[Journal_ref: ]
• , N. J., , O. G., , H. K., & , T. K. (2021). Application of Multicore Optical Fibers in Astronomy.
  More info

  Multicore fibers are gaining growing attention in astronomy. The two mainattributes which make them attractive for astronomy are that they reduce thedistance between cores and hence have a superior fill factor to otherapproaches and they offer the possibility to transport light in many channelswith the overhead of only having to handle a single fiber. These properties arebeing exploited to realize miniature integral field units that can transportlight from different regions in a focal plane to a spectrograph for example.Here we offer an overview of several applications where multicore fibers arenow being considered and applied to astronomical observations to enhancescientific yield.[Journal_ref: ]
• , O. G., & , J. M. (2021). Adaptive Optics Predictive Control with Empirical Orthogonal Functions (EOFs).
  More info

  Atmospheric wavefront prediction based on previous wavefront sensormeasurements can greatly enhance the performance of adaptive optics systems. Wepropose an optimal linear approach based on the Empirical Orthogonal Functions(EOF) framework commonly employed for atmospheric predictions. The approachoffers increased robustness and significant performance advantages overpreviously proposed wavefront prediction algorithms. It can be implemented as alinear pattern matching algorithm, which decomposes in real time the input(most recent wavefront sensor measurements) into a linear sum of previouslyencountered patterns, and uses the coefficients of this linear expansion topredict the future state. The process is robust against evolving conditions,unknown spatio-temporal correlations and non-periodic transient events, andenables multiple sensors (for example accelerometers) to contribute to thewavefront estimation. We illustrate the EOFs advantages through numericalsimulations, and demonstrate filter convergence within 1 minute on a 1 kHz ratesystem. We show that the EOFs approach provides significant gains in highcontrast imaging by simultaneously reducing residual speckle halo and producinga residual speckle halo that is spatially and temporally uncorrelated.[Journal_ref: ]
• , O. G., , B. M., , E. S., & , S. M. (2021). Optimal beam combiner design for nulling interferometers.
  More info

  A scheme to optimally design a beam combiner is discussed for anypre-determined fixed geometry nulling interferometer aimed at detection andcharacterization of exoplanets with multiple telescopes or a single telescope(aperture masking). We show that considerably higher order nulls can beachieved with 1-D interferometer geometries than possible with 2-D geometrieswith the same number of apertures. Any 1-D interferometer with N apertures canachieve a 2(N-1)-order null, while the order of the deepest null for a random2-D aperture geometry interferometer is the order of the N-th term in theTaylor expansion of e^{i(x^2+y^2)} around x=0, y=0 (2nd order null for N=2,3;4th order null for N=4,5,6). We also show that an optimal beam combiner fornulling interferometry relies only 0 or Pi phase shifts. Examples of nullinginterferometer designs are shown to illustrate these findings.[Journal_ref: ]
• , S. B., , A. Z., , R. B., , O. G., & , C. R. (2021). Detecting Exoplanets Using Eclipsing Binaries as Natural Starshades.
  More info

  We investigate directly imaging exoplanets around eclipsing binaries, usingthe eclipse as a natural tool for dimming the binary and thus increasing theplanet to star brightness contrast. At eclipse, the binary becomes point-like,making coronagraphy possible. We select binaries where the planet-star contrastwould be boosted by $>10\times$ during eclipse, making it possible to detect aplanet that is $\gtrsim10\times$ fainter or in a star system that is$\sim2$-$3\times$ more massive than otherwise. Our approach will yield insightsinto planet occurrence rates around binaries versus individual stars. Weconsider both self-luminous (SL) and reflected light (RL) planets. In the SLcase, we select binaries whose age is young enough so that an orbiting SLplanet would remain luminous; in U Cep and AC Sct, respectively, our method issensitive to SL planets of $\sim$4.5$M_J$ and $\sim$9$M_J$ with current ground-or near-future space-based instruments, and $\sim$1.5$M_J$ and $\sim$6$M_J$with future ground-based observatories. In the RL case, there are three nearby($\lesssim50$ pc) systems -- V1412 Aql, RR Cae, RT Pic -- around which aJupiter-like planet at a planet-star separation of $\gtrsim20$ mas might beimaged with future ground- and space-based coronagraphs. A Venus-like planet atthe same distance might be detectable around RR Cae and RT Pic. A habitableEarth-like planet represents a challenge; while the planet-star contrast ateclipse and planet flux are accessible with a 6-8m space telescope, theplanet-star separation is 1/3 - 1/4 of the angular separation limit of moderncoronagraphy.[Journal_ref: ]
• , T. C., , E. P., , R. B., & , O. G. (2021). Developing Linear Dark-Field Control for Exoplanet Direct Imaging in the Laboratory and on Ground-based Telescopes.
  More info

  Imaging rocky planets in reflected light, a key focus of future NASA missionsand ELTs, requires advanced wavefront control to maintain a deep, temporallycorrelated null of stellar halo at just several diffraction beam widths. Wediscuss development of Linear Dark Field Control (LDFC) to achieve this aim. Wedescribe efforts to test spatial LDFC in a laboratory setting for the firsttime, using the Ames Coronagraph Experiment (ACE) testbed. Our preliminaryresults indicate that spatial LDFC is a promising method focal-plane wavefrontcontrol method capable of maintaining a static dark hole, at least at contrastsrelevant for imaging mature planets with 30m-class telescopes.[Journal_ref: ]
• Anagnos, T., Trappen, M., Tiong, B., Feger, T., Yerolatsitis, S., Harris, R. J., Lozi, J., Jovanovic, N., Birks, T. A., Vievard, S., Guyon, O., Gris-S{\'anchez}, I., Leon-Saval, S. G., Norris, B., Haffert, S. Y., Hottinger, P., Blaicher, M., Xu, Y., Betters, C. H., , Koos, C., et al. (2021). 3D-M3: high-spatial-resolution spectroscopy with extreme AO and 3D-printed micro-lenslets. \ao, 60(19), D108.
• Bos, S., Miller, K., Lozi, J., Guyon, O., Doelman, D., Vievard, S., Sahoo, A., Deo, V., Jovanovic, N., Martinache, F., Currie, T., & Snik, F. (2021). First on-sky demonstration of spatial Linear Dark Field Control with the vector-Apodizing Phase Plate at Subaru/SCExAO. \aap, 653, A42.
• Chilcote, J., Tobin, T., Currie, T., Brandt, T. D., Groff, T. D., Kuzuhara, M., Guyon, O., Lozi, J., Jovanovic, N., Sahoo, A., Deo, V., Akiyama, E., Janson, M., Knapp, J., Kwon, J., McElwain, M. W., Nishikawa, J., Wagner, K., He{\lminiak}, K., , Skaf, N., et al. (2021). SCExAO/CHARIS Direct Imaging of A Low-mass Companion At A Saturn-like Separation from an Accelerating Young A7 Star. \aj, 162(6), 251.
• Doelman, D., Snik, F., Por, E., Bos, S., Otten, G., Kenworthy, M., Haffert, S., Wilby, M., Bohn, A., Sutlieff, B., Miller, K., Ouellet, M., Boer, J., Keller, C., Escuti, M., Shi, S., Warriner, N., Hornburg, K., Birkby, J., , Males, J., et al. (2021). Vector-apodizing phase plate coronagraph: design, current performance, and future development [Invited]. \ao, 60(19), D52.
• Gee, W., Guyon, O., Jovanovic, N., Schwab, C., Coutts, D., Walawender, J., & Mukherjea, A. (2021). On-sky demonstration of precision photometry with Bayer color filter arrays. Journal of Astronomical Telescopes, Instruments, and Systems, 7, 048001.
• Haffert, S. Y., Males, J. R., Close, L. M., Van, G. K., Long, J. D., Hedglen, A. D., Guyon, O., Schatz, L., Kautz, M., Lumbres, J., Rodack, A., Knight, J. M., Sun, H. e., & Fogarty, K. (2021). Data-driven subspace predictive control of adaptive optics for high-contrast imaging. Journal of Astronomical Telescopes, Instruments, and Systems, 7, 029001.
• Haffert, S. Y., Males, J. R., Close, L. M., Van, G. K., Long, J. D., Hedglen, A. D., Guyon, O., Schatz, L., Kautz, M., Lumbres, J., Rodack, A., Knight, J. M., Sun, H. e., & Fogarty, K. (2021). Data-driven subspace predictive control of adaptive optics for high-contrast imaging. arXiv e-prints, arXiv:2103.07566.
• Hart, G., Holstein, R. G., Bos, S. P., Ruigrok, J., Snik, F., Lozi, J., Guyon, O., Kudo, T., Zhang, J., Jovanovic, N., Norris, B., Martinod, M., Groff, T. D., Chilcote, J., Currie, T., Tamura, M., Vievard, S., Sahoo, A., Deo, V., , Ahn, K., et al. (2021). Full characterization of the instrumental polarization effects of the spectropolarimetric mode of SCExAO-CHARIS. arXiv e-prints, arXiv:2108.04833.
• Konishi, M., Matsuo, T., Yamamoto, K., Samland, M., Sudo, J., Shibai, H., Itoh, Y., Fukagawa, M., Sumi, T., Kudo, T., Hashimoto, J., Kuzuhara, M., Kusakabe, N., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Carson, J., Feldt, M., , Goto, M., et al. (2021). VizieR Online Data Catalog: Subaru NIR obs. of Pleiades stars in SEEDS survey (Konishi+, 2016). VizieR Online Data Catalog, J/PASJ/68/92.
• Lawson, K., Currie, T., Wisniewski, J. P., Tamura, M., Augereau, J., Brandt, T. D., Guyon, O., Kasdin, N. J., Groff, T. D., Lozi, J., Deo, V., Vievard, S., Chilcote, J., Jovanovic, N., Martinache, F., Skaf, N., Henning, T., Knapp, G., Kwon, J., , McElwain, M. W., et al. (2021). Multiband Imaging of the HD 36546 Debris Disk: A Refined View from SCExAO/CHARIS. \aj, 162(6), 293.
• Males, J. R., Fitzgerald, M. P., Belikov, R., & Guyon, O. (2021). The Mysterious Lives of Speckles. I. Residual Atmospheric Speckle Lifetimes in Ground-based Coronagraphs. \pasp, 133(1028), 104504.
• Martinod, M., Norris, B., Tuthill, P., Lagadec, T., Jovanovic, N., Cvetojevic, N., Gross, S., Arriola, A., Gretzinger, T., Withford, M. J., Guyon, O., Lozi, J., Vievard, S., Deo, V., Lawrence, J. S., & Leon-Saval, S. (2021). Scalable photonic-based nulling interferometry with the dispersed multi-baseline GLINT instrument. Nature Communications, 12, 2465.
• Miller, K., Bos, S., Lozi, J., Guyon, O., Doelman, D., Vievard, S., Sahoo, A., Deo, V., Jovanovic, N., Martinache, F., Snik, F., & Currie, T. (2021). Spatial linear dark field control on Subaru/SCExAO. Maintaining high contrast with a vAPP coronagraph. \aap, 646, A145.
• Rodack, A. T., Frazin, R. A., Males, J. R., & Guyon, O. (2021). Millisecond exoplanet imaging: I method and simulation results. Journal of the Optical Society of America A, 38(10), 1541.
• Skaf, N., Guyon, O., Boccaletti, A., Deo, V., Vievard, S., Lozi, J., Ahn, K., Norris, B., Currie, T., Gendron, E., Bertrou-Cantou, A., Ferreira, F., Sevin, A., & Vidal, F. (2021). High contrast imaging wavefront sensor referencing from coronagraphic images. arXiv e-prints, arXiv:2110.15361.
• Snellen, I. A., Snik, F., Kenworthy, M., Albrecht, S., Anglada-Escud{\'e}, G., Baraffe, I., Baudoz, P., Benz, W., Beuzit, J. -., Biller, B., Birkby, J., Boccaletti, A., Boekel, R., Boer, J., Brogi, M., Buchhave, L., Carone, L., Claire, M., Claudi, R., , Demory, B. -., et al. (2021). Detecting life outside our solar system with a large high-contrast-imaging mission. Experimental Astronomy.
• Steiger, S., Currie, T., Brandt, T. D., Guyon, O., Kuzuhara, M., Chilcote, J., Groff, T. D., Lozi, J., Walter, A. B., Fruitwala, N., Bailey, I., Zobrist, N., Swimmer, N., Lipartito, I., Smith, J. P., Bockstiegel, C., Meeker, S. R., Coiffard, G., Dodkins, R., , Szypryt, P., et al. (2021). SCExAO/MEC and CHARIS Discovery of a Low Mass, 6 AU-Separation Companion to HIP 109427 using Stochastic Speckle Discrimination and High-Contrast Spectroscopy. arXiv e-prints, arXiv:2103.06898.
• Steiger, S., Currie, T., Brandt, T. D., Guyon, O., Kuzuhara, M., Chilcote, J., Groff, T. D., Lozi, J., Walter, A. B., Fruitwala, N., Bailey, I., Zobrist, N., Swimmer, N., Lipartito, I., Smith, J. P., Bockstiegel, C., Meeker, S. R., Coiffard, G., Dodkins, R., , Szypryt, P., et al. (2021). SCExAO/MEC and CHARIS Discovery of a Low-mass, 6 au Separation Companion to HIP 109427 Using Stochastic Speckle Discrimination and High-contrast Spectroscopy. \aj, 162(2), 44.
• Steiger, S., Currie, T., Brandt, T., Guyon, O., Kuzuhara, M., Chilcote, J., Groff, T., Lozi, J., Walter, A., Fruitwala, N., Bailey, I., Zobrist, N., Swimmer, N., Lipartito, I., Smith, J., Bockstiegel, C., Meeker, S., Coiffard, G., Dodkins, R., , Szypryt, P., et al. (2021). VizieR Online Data Catalog: Near-IR spectrum of HIP 109427 with SCExAO/CHARIS (Steiger+, 2021). VizieR Online Data Catalog, J/AJ/162/44.
• Van, G. K., Males, J. R., Close, L. M., Lumbres, J., Hedglen, A., Long, J. D., Haffert, S. Y., Guyon, O., Kautz, M., Schatz, L., Miller, K., Rodack, A. T., Knight, J. M., & Morzinski, K. M. (2021). Characterizing deformable mirrors for the MagAO-X instrument. Journal of Astronomical Telescopes, Instruments, and Systems, 7, 039001.
• Wagner, K., Boehle, A., Pathak, P., Kasper, M., Arsenault, R., Jakob, G., K{\"aufl}, U., Leveratto, S., Maire, A. -., Pantin, E., Siebenmorgen, R., Zins, G., Absil, O., Ageorges, N., Apai, D., Carlotti, A., Choquet, \., Delacroix, C., Dohlen, K., , Duhoux, P., et al. (2021). Imaging low-mass planets within the habitable zone of \ensuremath{\alpha} Centauri. Nature Communications, 12, 922.
• Wong, A. P., Norris, B. R., Tuthill, P. G., Scalzo, R., Lozi, J., Vievard, S., & Guyon, O. (2021). Predictive control for adaptive optics using neural networks. Journal of Astronomical Telescopes, Instruments, and Systems, 7, 019001.
• Bellotti, S., Zabludoff, A. I., Belikov, R., Guyon, O., & Rathi, C. (2020). Detecting Exoplanets Using Eclipsing Binaries as Natural Starshades. \aj, 160(3), 131.
• Bellotti, S., Zabludoff, A., Belikov, R., Guyon, O., & Rathi, C. (2020). VizieR Online Data Catalog: Compilation of 289 eclipsing binaries parameters (Bellotti+, 2020). VizieR Online Data Catalog, J/AJ/160/131.
• Bond, C. Z., Cetre, S., Lilley, S., Wizinowich, P., Mawet, D., Chun, M., Wetherell, E., Jacobson, S., Lockhart, C., Warmbier, E., Ragland, S., Alvarez, C., Guyon, O., Goebel, S., Delorme, J., Jovanovic, N., Hall, D. N., Wallace, J. K., Taheri, M., , Plantet, C., et al. (2020). Adaptive optics with an infrared pyramid wavefront sensor at Keck. Journal of Astronomical Telescopes, Instruments, and Systems, 6, 039003.
• Bos, S., Vievard, S., Wilby, M., Snik, F., Lozi, J., Guyon, O., Norris, B., Jovanovic, N., Martinache, F., Sauvage, J. -., & Keller, C. (2020). On-sky verification of Fast and Furious focal-plane wavefront sensing: Moving forward toward controlling the island effect at Subaru/SCExAO. \aap, 639, A52.
• Close, L. M., Males, J. R., Hedglen, A., Bouchez, A., & Guyon, O. (2020). Concept for the GMT High-Contrast Exoplanet Instrument GMagAO-X and the GMT High-Contrast Phasing Testbed with MagAO-X. arXiv e-prints, arXiv:2004.06808.
• Currie, T., Brandt, T. D., Kuzuhara, M., Chilcote, J., Guyon, O., Marois, C., Groff, T. D., Lozi, J., Vievard, S., Sahoo, A., Deo, V., Jovanovic, N., Martinache, F., Wagner, K., Dupuy, T., Wahl, M., Letawsky, M., Li, Y., Zeng, Y., , Brandt, G. M., et al. (2020). SCExAO/CHARIS Direct Imaging Discovery of a 20 au Separation, Low-mass Ratio Brown Dwarf Companion to an Accelerating Sun-like Star. \apjl, 904(2), L25.
• Currie, T., Pluzhnik, E., Guyon, O., Belikov, R., Miller, K., Bos, S., Males, J., Sirbu, D., Bond, C., Frazin, R., Groff, T., Kern, B., Lozi, J., Mazin, B. A., Nemati, B., Norris, B., Subedi, H., & Will, S. (2020). Laboratory Demonstration of Spatial Linear Dark Field Control For Imaging Extrasolar Planets in Reflected Light. \pasp, 132(1016), 104502.
• Gaudi, B. S., Seager, S., Mennesson, B., Kiessling, A., Warfield, K., Cahoy, K., Clarke, J. T., Domagal-Goldman, S., Feinberg, L., Guyon, O., Kasdin, J., Mawet, D., Plavchan, P., Robinson, T., Rogers, L., Scowen, P., Somerville, R., Stapelfeldt, K., Stark, C., , Stern, D., et al. (2020). The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Final Report. arXiv e-prints, arXiv:2001.06683.
• Laugier, R., Martinache, F., Cvetojevic, N., Mary, D., Ceau, A., N'Diaye, M., Kammerer, J., Lozi, J., Guyon, O., & Lopez, C. (2020). Angular differential kernel phases. \aap, 636, A21.
• Lawson, K., Currie, T., Wisniewski, J. P., Tamura, M., Schneider, G., Augereau, J., Brandt, T. D., Guyon, O., Kasdin, N. J., Groff, T. D., Lozi, J., Chilcote, J., Hodapp, K., Jovanovic, N., Martinache, F., Skaf, N., Akiyama, E., Henning, T., Knapp, G. R., , Kwon, J., et al. (2020). SCExAO/CHARIS Near-infrared Integral Field Spectroscopy of the HD 15115 Debris Disk. \aj, 160(4), 163.
• Martinez, P., Beaulieu, M., Barjot, K., Guyon, O., Gouvret, C., Marcotto, A., Belhadi, M., Caillat, A., Behaghel, T., Tisserand, S., Sauget, V., Gautier, S., Le, D. J., Knight, J., Dohlen, K., Vigan, A., Abe, L., Preis, O., Spang, A., , Dejonghe, J., et al. (2020). Design and manufacturing of a multi-zone phase-shifting coronagraph mask for extremely large telescopes. \aap, 635, A126.
• Mayama, S., P{\'erez}, S., Kusakabe, N., Muto, T., Tsukagoshi, T., Sitko, M. L., Takami, M., Hashimoto, J., Dong, R., Kwon, J., Hayashi, S. S., Kudo, T., Kuzuhara, M., Follette, K., Fukagawa, M., Momose, M., Oh, D., Leon, J., Akiyama, E., , Wisniewski, J. P., et al. (2020). Subaru Near-infrared Imaging Polarimetry of Misaligned Disks around the SR 24 Hierarchical Triple System. \aj, 159(1), 12.
• Norris, B. R., Cvetojevic, N., Lagadec, T., Jovanovic, N., Gross, S., Arriola, A., Gretzinger, T., Martinod, M., Guyon, O., Lozi, J., Withford, M. J., Lawrence, J. S., & Tuthill, P. (2020). First on-sky demonstration of an integrated-photonic nulling interferometer: the GLINT instrument. \mnras, 491(3), 4180-4193.
• Sahoo, A., Guyon, O., Lozi, J., Chilcote, J., Jovanovic, N., Brandt, T., Groff, T., & Martinache, F. (2020). Precision Photometric and Astrometric Calibration Using Alternating Satellite Speckles. \aj, 159(6), 250.
• Uyama, T., Currie, T., Christiaens, V., Bae, J., Muto, T., Takahashi, S. Z., Tazaki, R., Ygouf, M., Kasdin, J. N., Groff, T., Brandt, T. D., Chilcote, J., Hayashi, M., McElwain, M. W., Guyon, O., Lozi, J., Jovanovic, N., Martinache, F., Kudo, T., , Tamura, M., et al. (2020). SCExAO/CHARIS High-contrast Imaging of Spirals and Darkening Features in the HD 34700 A Protoplanetary Disk. \apj, 900(2), 135.
• Uyama, T., Currie, T., Hori, Y., De, R., Mede, K., Brandt, T. D., Kwon, J., Guyon, O., Lozi, J., Jovanovic, N., Martinache, F., Kudo, T., Tamura, M., Kasdin, N. J., Groff, T., Chilcote, J., Hayashi, M., McElwain, M. W., Asensio-Torres, R., , Janson, M., et al. (2020). Atmospheric Characterization and Further Orbital Modeling of \ensuremath{\kappa} Andromeda b. \aj, 159(2), 40.
• Uyama, T., Norris, B., Jovanovic, N., Lozi, J., Tuthill, P., Guyon, O., Kudo, T., Hashimoto, J., Tamura, M., & Martinache, F. (2020). High-contrast H\ensuremath{\alpha} imaging with Subaru/SCExAO + VAMPIRES. Journal of Astronomical Telescopes, Instruments, and Systems, 6, 045004.
• Uyama, T., Ren, B., Mawet, D., Ruane, G., Bond, C. Z., Hashimoto, J., Liu, M. C., Muto, T., Ruffio, J., Wallack, N., Baranec, C., Bowler, B. P., Choquet, E., Chun, M., Delorme, J., Fogarty, K., Guyon, O., Jensen-Clem, R., Meshkat, T., , Ngo, H., et al. (2020). Early High-contrast Imaging Results with Keck/NIRC2-PWFS: The SR 21 Disk. \aj, 160(6), 283.
• Vievard, S., Cvetojevic, N., Huby, E., Lacour, S., Martin, G., Guyon, O., Lozi, J., Kotani, T., Jovanovic, N., Perrin, G., Marchis, F., Lai, O., Lapeyrere, V., & Rouan, D. (2020). Capabilities of a fibered imager on an extremely large telescope. arXiv e-prints, arXiv:2010.10733.
• Walter, A. B., Fruitwala, N., Steiger, S., Bailey, I., Zobrist, N., Swimmer, N., Lipartito, I., Smith, J. P., Meeker, S. R., Bockstiegel, C., Coiffard, G., Dodkins, R., Szypryt, P., Davis, K. K., Daal, M., Bumble, B., Collura, G., Guyon, O., Lozi, J., , Vievard, S., et al. (2020). The MKID Exoplanet Camera for Subaru SCExAO. \pasp, 132(1018), 125005.
• Wang, J. J., Ginzburg, S., Ren, B., Wallack, N., Gao, P., Mawet, D., Bond, C. Z., Cetre, S., Wizinowich, P., De, R., Ruane, G., Liu, M. C., Absil, O., Alvarez, C., Baranec, C., Choquet, \., Chun, M., Defr{\`ere}, D., Delorme, J., , Duch{\^ene}, G., et al. (2020). Keck/NIRC2 L'-band Imaging of Jovian-mass Accreting Protoplanets around PDS 70. \aj, 159(6), 263.
• Wang, J. i., Wang, J. J., Ma, B. o., Chilcote, J., Ertel, S., Guyon, O., Ilyin, I., Jovanovic, N., Kalas, P., Lozi, J., Macintosh, B., Strassmeier, K. G., & Stone, J. (2020). On the Chemical Abundance of HR 8799 and the Planet c. \aj, 160(3), 150.
• Yang, Y. i., Akiyama, E., Currie, T., Dong, R., Hashimoto, J., Hayashi, S. S., Grady, C. A., Janson, M., Jovanovic, N., Uyama, T., Nakagawa, T., Kudo, T., Kusakabe, N., Kuzuhara, M., Abe, L., Brandner, W., Brandt, T. D., Bonnefoy, M., Carson, J. C., , Chilcote, J., et al. (2020). High-resolution Near-infrared Polarimetry and Submillimeter Imaging of FS Tau A: Possible Streamers in Misaligned Circumbinary Disk System. \apj, 889(2), 140.
• Asensio-Torres, R., Currie, T., Janson, M., Desidera, S., Kuzuhara, M., Hodapp, K., Brandt, T. D., Guyon, O., Lozi, J., Groff, T., Kasdin, J., Chilcote, J., Jovanovic, N., Martinache, F., Sitko, M., Serabyn, E., Wagner, K., Akiyama, E., Kwon, J., , Uyama, T., et al. (2019). Isochronal age-mass discrepancy of young stars: SCExAO/CHARIS integral field spectroscopy of the HIP 79124 triple system. aap, 622, A42.
• Belikov, R., Barclay, T., Batalha, N. M., Bendek, E., Bolcar, M., Chakrabarti, S., Currie, T., Goldblatt, C., Guyon, O., Kasdin, N. J., Kasting, J., Kern, B. D., Lissauer, J. J., Lozi, J., Macintosh, B., Mennesson, B., Males, J. R., Marchis, F., Marley, M. S., , Marois, C., et al. (2019). Direct Imaging of Exoplanets in Nearby Multi-Star Systems. baas, 51(3), 517.
• Bendek, E., Belikov, R., Guyon, O., Currie, T., Hasegawa, Y., Marley, M. S., Martin, S., Menesson, B., Shao, M., Turyshev, S., Vasisht, G., Tuthill, P., McArthur, B. E., Rogers, L., & Van, B. G. (2019). The value of astrometry for exoplanet science. baas, 51(3), 354.
• Bos, S., Doelman, D., Lozi, J., Guyon, O., Keller, C., Miller, K., Jovanovic, N., Martinache, F., & Snik, F. (2019). Focal-plane wavefront sensing with the vector-Apodizing Phase Plate. aap, 632, A48.
• Brandt, T., Briesemeister, Z., Savransky, D., Fitzgerald, M., Mazin, B., Fortney, J., Dupuy, T., Bowler, B., Sallum, S., Mawet, D., Skemer, A., Vasisht, G., Miller-Blanchard, M., Wang, J., Guyon, O., Meshkat, T., Jensen-Clem, R., Serabyn, E., Ruane, G., , Liu, M., et al. (2019). Realizing the Promise of High-Contrast Imaging: More Than 100 Gas-Giant Planets with Masses, Orbits, and Spectra Enabled by Gaia+WFIRST Astrometry. baas, 51(3), 269.
• Currie, T., Belikov, R., Guyon, O., Kasdin, N. J., Marois, C., Marley, M. S., Cahoy, K., Mawet, D., McElwain, M., Bendek, E., Kuchner, M. J., & Meyer, M. R. (2019). The Critical Strategic Importance of Adaptive Optics-Assisted Ground-Based Telescopes for the Success of Future NASA Exoplanet Direct Imaging Missions. baas, 51(3), 154.
• Currie, T., Guyon, O., Lozi, J., Groff, T., Kasdin, N. J., Martinache, F., {Brand, t., Chilcote, J., Marois, C., Gerard, B., Jovanovic, N., & Vievard, S. (2019). Performance and Early Science with the Subaru Coronagraphic Extreme Adaptive Optics Project. arXiv e-prints, arXiv:1909.10522.
• Currie, T., Marois, C., Cieza, L., Mulders, G. D., Lawson, K., Caceres, C., Rodriguez-Ruiz, D., Wisniewski, J., Guyon, O., Brandt, T. D., Kasdin, N. J., Groff, T. D., Lozi, J., Chilcote, J., Hodapp, K., Jovanovic, N., Martinache, F., Skaf, N., Lyra, W., , Tamura, M., et al. (2019). No Clear, Direct Evidence for Multiple Protoplanets Orbiting LkCa 15: LkCa 15 bcd are Likely Inner Disk Signals. apjl, 877(1), L3.
• Currie, T., Pluzhnik, E., Belikov, R., & Guyon, O. (2019). Developing Linear Dark-Field Control for Exoplanet Direct Imaging in the Laboratory and on Ground-based Telescopes. arXiv e-prints, arXiv:1909.11664.
• Douglas, E., Males, J., Clark, J., Guyon, O., Lumbres, J., Marlow, W., & Cahoy, K. (2019). Laser Guide Star for Large Segmented-aperture Space Telescopes. I. Implications for Terrestrial Exoplanet Detection and Observatory Stability. aj, 157(1), 36.
• Gerard, B. L., Marois, C., Currie, T., Brandt, T., Chilcote, J. K., Draper, Z. H., Groff, T., Guyon, O., Hayashi, M., Jovanovic, N., Knapp, G. R., Kudo, T., Kwon, J., Lozi, J., Martinache, F., McElwain, M., Tamura, M., & Uyama, T. (2019). A Chromaticity Analysis and PSF Subtraction Techniques for SCExAO/CHARIS Data. aj, 158(1), 36.
• Kasper, M., Arsenault, R., K{"aufl}, U., Jakob, G., Leveratto, S., Zins, G., Pantin, E., Duhoux, P., Riquelme, M., Kirchbauer, J. -., Kolb, J., Pathak, P., Siebenmorgen, R., Soenke, C., Fuenteseca, E., Sterzik, M., Ageorges, N., Gutruf, S., Kampf, D., , Reutlinger, A., et al. (2019). NEAR: First Results from the Search for Low-Mass Planets in ensuremath{alpha} Cen. The Messenger, 178, 5-9.
• Lozi, J., Jovanovic, N., Guyon, O., Chun, M., Jacobson, S., Goebel, S., & Martinache, F. (2019). Visible and Near Infrared Laboratory Demonstration of a Simplified Pyramid Wavefront Sensor. pasp, 131(998), 044503.
• Marley, M., Lewis, N., Arney, G., Bailey, V., Batalha, N., Beichman, C., Benneke, B., Blecic, J., Cahoy, K., Chilcote, J., Domagal-Goldman, S., Dressing, C., Fitzgerald, M., Fortney, J., Freedman, R., Gelino, D., Gizis, J., Guyon, O., Greene, T., , Hammel, H., et al. (2019). Imaging Cool Giant Planets in Reflected Light: Science Investigations and Synergy with Habitable Planets. baas, 51(3), 345.
• Mazin, B., Artigau, E., Bailey, V., Baranec, C., Beichman, C., Benneke, B., Birkby, J., Brandt, T., Chilcote, J., Chun, M., Close, L., Currie, T., Crossfield, I., Dekany, R., Delorme, J., Dong, C., Dong, R., Doyon, R., Dressing, C., , Fitzgerald, M., et al. (2019). Directly Imaging Rocky Planets from the Ground. baas, 51(3), 128.
• Miller, K., Males, J. R., Guyon, O., Close, L. M., Doelman, D., Snik, F., Por, E., Wilby, M. J., Keller, C., Bohlman, C., Van, G. K., Rodack, A., Knight, J., Lumbres, J., Bos, S., & Jovanovic, N. (2019). Spatial linear dark field control and holographic modal wavefront sensing with a vAPP coronagraph on MagAO-X. Journal of Astronomical Telescopes, Instruments, and Systems, 5, 049004.
• Rich, E. A., Wisniewski, J. P., Currie, T., Fukagawa, M., Grady, C. A., Sitko, M. L., Pikhartova, M., Hashimoto, J., Abe, L., {Brand, n. W., Brandt, T. D., Carson, J. C., Chilcote, J., Dong, R., Feldt, M., Goto, M., Groff, T., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2019). Multi-epoch Direct Imaging and Time-variable Scattered Light Morphology of the HD 163296 Protoplanetary Disk. apj, 875(1), 38.
• Shao, M., Turyshev, S. G., Zhai, C., Vasisht, G., Bendek, E., Fischer, D., Guyon, O., McArthur, B., Muterspaugh, M., & Boehm, C. (2019). Finding Exo-Earths with Precision Space Astrometry. baas, 51(3), 74.
• Snellen, I., Albrecht, S., Anglada-Escude, G., Baraffe, I., Baudoz, P., Benz, W., Beuzit, J., Biller, B., Birkby, J., Boccaletti, A., Boekel, R., Boer, J., Brogi, M., Buchhave, L., Carone, L., Claire, M., Claudi, R., Demory, B., Desert, J., , Desidera, S., et al. (2019). ESA Voyage 2050 White Paper: Detecting life outside our solar system with a large high-contrast-imaging mission. arXiv e-prints, arXiv:1908.01803.
• Vievard, S., Bos, S., Cassaing, F., Ceau, A., Guyon, O., Jovanovic, N., Keller, C. U., Lozi, J., Martinache, F., Montmerle-Bonnefois, A., Mugnier, L., NDiaye, M., Norris, B., Sahoo, A., Sauvage, J., Snik, F., Wilby, M. J., & Wong, A. (2019). Overview of focal plane wavefront sensors to correct for the Low Wind Effect on SUBARU/SCExAO. arXiv e-prints, arXiv:1912.10179.
• Bendek, E., Belikov, R., Guyon, O., Greene, T., Pluzhnik, E., Milster, T., Rodack, A., Finan, E., & Knight, J. (2018). TDEM final report: Enhanced direct imaging exoplanet detection with astrometry mass determination. arXiv e-prints, arXiv:1805.06933.
• Bendek, E., Belikov, R., Guyon, O., Greene, T., Pluzhnik, E., Milster, T., Rodack, A., Finan, E., & Knight, J. (2018). TDEM final report: Enhanced direct imaging exoplanet detection with astrometry mass determination. arXiv e-prints.
• Bendek, E., Marley, M., Shao, M., Guyon, O., Belikov, R., & Tuthill, P. (2018). The value of astrometry for exoplanet science. arXiv e-prints.
• Currie, T., Belikov, R., Guyon, O., Kasdin, N. J., Marois, C., Marley, M., Cahoy, K., McElwain, M., Bendek, E., Kuchner, M., & Meyer, M. (2018). Using Ground-Based Telescopes to Mature Key Technologies and Advance Science for Future NASA Exoplanet Direct Imaging Missions. arXiv e-prints, arXiv:1803.05453.
• Currie, T., Belikov, R., Guyon, O., Kasdin, N., Marois, C., Marley, M., Cahoy, K., McElwain, M., Bendek, E., Kuchner, M., & Meyer, M. (2018). Using Ground-Based Telescopes to Mature Key Technologies and Advance Science for Future NASA Exoplanet Direct Imaging Missions. arXiv e-prints.
• Currie, T., Brandt, T., Uyama, T., Nielsen, E., Blunt, S., Guyon, O., Tamura, M., Marois, C., Mede, K., Kuzuhara, M., Groff, T., Jovanovic, N., Kasdin, N., Lozi, J., Hodapp, K., Chilcote, J., Carson, J., Martinache, F., Goebel, S., , Grady, C., et al. (2018). SCExAO/CHARIS Near-infrared Direct Imaging, Spectroscopy, and Forward-Modeling of $\kappa$ And b: A Likely Young, Low-gravity Superjovian Companion. \aj, 156, 291.
• Currie, T., Kasdin, N., Groff, T., Lozi, J., Jovanovic, N., Guyon, O., Brandt, T., Martinache, F., Chilcote, J., Skaf, N., Kuhn, J., Pathak, P., & Kudo, T. (2018). Laboratory and On-sky Validation of the Shaped Pupil Coronagraph\rsquos Sensitivity to Low-order Aberrations With Active Wavefront Control. \pasp, 130(4), 044505.
• Donnot, B., Guyon, I., Schoenauer, M., Marot, A., & Panciatici, P. (2018). Anticipating contingengies in power grids using fast neural net screening. arXiv e-prints.
• Donnot, B., Guyon, I., Schoenauer, M., Marot, A., & Panciatici, P. (2018). Fast Power system security analysis with Guided Dropout. arXiv e-prints.
• Farinato, J., Bacciotti, F., Baffa, C., Baruffolo, A., Bergomi, M., Bianco, A., Bongiorno, A., Carbonaro, L., Carolo, E., Carlotti, A., Chinellato, S., Close, L., De Pascale, M., Dima, M., D'Orazi, V., Esposito, S., Fantinel, D., Farisato, G., Gaessler, W., , Giallongo, E., et al. (2018). SHARK-NIR, the coronagraphic camera for LBT, moving toward construction. arXiv e-prints.
• Farinato, J., Bacciotti, F., Baffa, C., Baruffolo, A., Bergomi, M., Bianco, A., Bongiorno, A., Carbonaro, L., Carolo, E., Carlotti, A., Chinellato, S., Close, L., De, P. M., Dima, M., D'Orazi, V., Esposito, S., Fantinel, D., Farisato, G., Gaessler, W., , Giallongo, E., et al. (2018). SHARK-NIR, the coronagraphic camera for LBT, moving toward construction. arXiv e-prints, arXiv:1808.00364.
• Gaudi, B. S., Seager, S., Mennesson, B., Kiessling, A., Warfield, K., Kuan, G., Cahoy, K., Clarke, J. T., Domagal-Goldman, S., Feinberg, L., Guyon, O., Kasdin, J., Mawet, D., Robinson, T., Rogers, L., Scowen, P., Somerville, R., Stapelfeldt, K., Stark, C., , Stern, D., et al. (2018). The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Interim Report. arXiv e-prints, arXiv:1809.09674.
• Gaudi, B., Seager, S., Mennesson, B., Kiessling, A., Warfield, K., Kuan, G., Cahoy, K., Clarke, J., Domagal-Goldman, S. .., Feinberg, L., Guyon, O., Kasdin, J., Mawet, D., Robinson, T., Rogers, L., Scowen, P., Somerville, R., Stapelfeldt, K., Stark, C., , Stern, D., et al. (2018). The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Interim Report. arXiv e-prints.
• Goebel, S., Currie, T., Guyon, O., Brandt, T., Groff, T., Jovanovic, N., Kasdin, N., Lozi, J., Hodapp, K., Martinache, F., Grady, C., Hayashi, M., Kwon, J., McElwain, M., Yang, Y., & Tamura, M. (2018). SCExAO/CHARIS Near-IR High-contrast Imaging and Integral Field Spectroscopy of the HIP 79977 Debris Disk. \aj, 156, 279.
• Goebel, S., Guyon, O., Hall, D., Jovanovic, N., Lozi, J., & Martinache, F. (2018). Measurements of Speckle Lifetimes in Near-infrared Extreme Adaptive Optics Images for Optimizing Focal Plane Wavefront Control. \pasp, 130(10), 104502.
• Goebel, S., Hall, D., Guyon, O., Warmbier, E., & Jacobson, S. (2018). Overview of the SAPHIRA detector for adaptive optics applications. Journal of Astronomical Telescopes, Instruments, and Systems, 4(2), 026001.
• Guyon, O. (2018). Extreme Adaptive Optics. \araa, 56, 315-355.
• Jair Escalante, H., Kaya, H., Salah, A., Escalera, S., Gucluturk, Y., Guclu, U., Baro, X., Guyon, I., Junior, J., Madadi, M., Ayache, S., Viegas, E., Gurpinar, F., Sukma Wicaksana, A., Liem, C., Gerven, M., & Lier, R. (2018). Explaining First Impressions: Modeling, Recognizing, and Explaining Apparent Personality from Videos. arXiv e-prints.
• Junior, J., G{\"u\c, c. Y., P{\'erez}, M., G{\"u\c, c. U., Andujar, C., Bar{\'o}, X., Jair Escalante, H., Guyon, I., Gerven, M., Lier, R., & Escalera, S. (2018). First Impressions: A Survey on Vision-Based Apparent Personality Trait Analysis. arXiv e-prints.
• K{\"uhn}, J., Serabyn, E., Lozi, J., Jovanovic, N., Currie, T., Guyon, O., Kudo, T., Martinache, F., Liewer, K., Singh, G., Tamura, M., Mawet, D., Hagelberg, J., & Defrere, D. (2018). An H-band Vector Vortex Coronagraph for the Subaru Coronagraphic Extreme-adaptive Optics System. \pasp, 130(3), 035001.
• Lozi, J., Guyon, O., Jovanovic, N., Takato, N., Singh, G., Norris, B., Okita, H., Bando, T., & Martinache, F. (2018). Characterizing Vibrations at the Subaru Telescope for the Subaru Coronagraphic Extreme Adaptive Optics instrument. arXiv e-prints.
• Lozi, J., Guyon, O., Jovanovic, N., Takato, N., Singh, G., Norris, B., Okita, H., Bando, T., & Martinache, F. (2018). Characterizing vibrations at the Subaru Telescope for the Subaru coronagraphic extreme adaptive optics instrument. Journal of Astronomical Telescopes, Instruments, and Systems, 4, 049001.
• Males, J., & Guyon, O. (2018). Ground-based adaptive optics coronagraphic performance under closed-loop predictive control. Journal of Astronomical Telescopes, Instruments, and Systems, 4(1), 019001.
• Meyer, M. R., Currie, T., Guyon, O., Hasegawa, Y., Kasper, M., Marois, C., Monnier, J., Morzinski, K., Packham, C., & Quanz, S. (2018). Finding and Characterizing Other Worlds: the Thermal-IR ELT Opportunity. arXiv e-prints, arXiv:1804.03218.
• Meyer, M., Currie, T., Guyon, O., Hasegawa, Y., Kasper, M., Marois, C., Monnier, J., Morzinski, K., Packham, C., & Quanz, S. (2018). Finding and Characterizing Other Worlds: the Thermal-IR ELT Opportunity. arXiv e-prints.
• Mizuki, T., Kuzuhara, M., Mede, K., Schlieder, J., Janson, M., Brandt, T., Hirano, T., Narita, N., Wisniewski, J., Yamada, T., Biller, B., Bonnefoy, M., Carson, J., McElwain, M., Matsuo, T., Turner, E., Mayama, S., Akiyama, E., Uyama, T., , Nakagawa, T., et al. (2018). Orbital Characterization of GJ1108A System, and Comparison of Dynamical Mass with Model-derived Mass for Resolved Binaries. \apj, 865, 152.
• Morse, J., Bendek, E., Cabrol, N., Marchis, F., Turnbull, M., Chakrabarti, S., Fischer, D., Goldblatt, C., Guyon, O., Hart, M., Males, J., & Kasting, J. (2018). Project Blue: Visible Light Imaging Search for Terrestrial-class Exoplanets in the Habitable Zones of Alpha Centauri A and B. arXiv e-prints, arXiv:1803.04872.
• Morse, J., Bendek, E., Cabrol, N., Marchis, F., Turnbull, M., Chakrabarti, S., Fischer, D., Goldblatt, C., Guyon, O., Hart, M., Males, J., & Kasting, J. (2018). Project Blue: Visible Light Imaging Search for Terrestrial-class Exoplanets in the Habitable Zones of Alpha Centauri A and B. arXiv e-prints.
• N'Diaye, M., Martinache, F., Jovanovic, N., Lozi, J., Guyon, O., Norris, B., Ceau, A., & Mary, D. (2018). Calibration of the island effect: Experimental validation of closed-loop focal plane wavefront control on Subaru/SCExAO. \aap, 610, A18.
• Pathak, P., Guyon, O., Jovanovic, N., Lozi, J., Martinache, F., Minowa, Y., Kudo, T., Kotani, T., & Takami, H. (2018). On-sky Closed-loop Correction of Atmospheric Dispersion for High-contrast Coronagraphy and Astrometry. \pasp, 130(2), 025004.
• Shao, M., Turyshev, S. G., Bendek, E., Fischer, D., Guyon, O., McArthur, B., Muterspaugh, M., Zhai, C., & Boehm, C. (2018). Precision Space Astrometry as a Tool to Find Earth-like Exoplanets. arXiv e-prints, arXiv:1803.03732.
• Shao, M., Turyshev, S., Bendek, E., Fischer, D., Guyon, O., McArthur, B., Muterspaugh, M., Zhai, C., & Boehm, C. (2018). Precision Space Astrometry as a Tool to Find Earth-like Exoplanets. arXiv e-prints.
• Sherwood Lollar, B., Atreya, S., Boss, A., Falkowski, P., Farmer, J., Guyon, O., Joyce, G., Kasting, J., Meadows, V., Neches, P., Pilcher, C., Renno, N., Rogers, K., Schmidt, B., Summons, R., Westall, F., & Wright, S. (2018). Astrobiology Science Strategy for the Search for Life in the Universe. AGU Fall Meeting Abstracts.
• Trumper, I., Hallibert, P., Arenberg, J. W., Kunieda, H., Guyon, O., Stahl, H. P., & Kim, D. W. (2018). Optics technology for large-aperture space telescopes: from fabrication to final acceptance tests. Advances in Optics and Photonics, 10(3), 644.
• Uyama, T., Hashimoto, J., Muto, T., Akiyama, E., Dong, R., Leon, J., Sakon, I., Kudo, T., Kusakabe, N., Kuzuhara, M., Bonnefoy, M., Abe, L., Brandner, W., Brandt, T., Carson, J., Currie, T., Egner, S., Feldt, M., Fung, J., , Goto, M., et al. (2018). Subaru/HiCIAO HK $_s$ Imaging of LKHa 330: Multi-band Detection of the Gap and Spiral-like Structures. \aj, 156, 63.
• Yang, Y., Mayama, S., Hayashi, S., Hashimoto, J., Rafikov, R., Akiyama, E., Currie, T., Janson, M., Momose, M., Nakagawa, T., Oh, D., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., , Goto, M., et al. (2018). High-contrast Polarimetry Observation of the T Tau Circumstellar Environment. \apj, 861, 133.
• Brandt, T., McElwain, M., Turner, E., Mede, K., Spiegel, D., Kuzuhara, M., Schlieder, J., Wisniewski, J., Abe, L., Biller, B., Brandner, W., Carson, J., Currie, T., Egner, S., Feldt, M., Golota, T., Goto, M., Grady, C., Guyon, O., , Hashimoto, J., et al. (2017). "VizieR Online Data Catalog: Statistical analysis of exoplanet surveys (Brandt+, 2014)". VizieR Online Data Catalog, 179.
• Brandt, T., McElwain, M., Turner, E., Mede, K., Spiegel, D., Kuzuhara, M., Schlieder, J., Wisniewski, J., Abe, L., Biller, B., Brandner, W., Carson, J., Currie, T., Egner, S., Feldt, M., Golota, T., Goto, M., Grady, C., Guyon, O., , Hashimoto, J., et al. (2017). VizieR Online Data Catalog: Statistical analysis of exoplanet surveys (Brandt+, 2014). VizieR Online Data Catalog, J/ApJ/794/159.
• Currie, T., Guyon, O., Tamura, M., Kudo, T., Jovanovic, N., Lozi, J., Schlieder, J. E., Brandt, T. D., Kuhn, J., Serabyn, E., Janson, M., Carson, J., Groff, T., Kasdin, N. J., McElwain, M. W., Singh, G., Uyama, T., Kuzuhara, M., Akiyama, E., , Grady, C., et al. (2017). Subaru/SCExAO First-light Direct Imaging of a Young Debris Disk around HD 36546. \apjl, 836(1), L15.
• Currie, T., Guyon, O., Tamura, M., Kudo, T., Jovanovic, N., Lozi, J., Schlieder, J., Brandt, T., Kuhn, J., Serabyn, E., Janson, M., Carson, J., Groff, T., Kasdin, N., McElwain, M., Singh, G., Uyama, T., Kuzuhara, M., Akiyama, E., , Grady, C., et al. (2017). "Subaru/SCExAO First-light Direct Imaging of a Young Debris Disk around HD 36546". apjl, 836, L15.
• Cvetojevic, N., Jovanovic, N., Gross, S., Norris, B., Spaleniak, I., Schwab, C., Withford, M., Ireland, M., Tuthill, P., Guyon, O., Martinache, F., & Lawrence, J. (2017). "Modal noise in an integrated photonic lantern fed diffraction-limited spectrograph". Optics Express, 25, 25546.
• Garcia, E. V., Currie, T., Guyon, O., Stassun, K. G., Jovanovic, N., Lozi, J., Kudo, T., Doughty, D., Schlieder, J., Kwon, J., Uyama, T., Kuzuhara, M., Carson, J., Nakagawa, T., Hashimoto, J., Kusakabe, N., Abe, L., Brandner, W., Brandt, T., , Feldt, M., et al. (2017). SCExAO and GPI Y JHBand Photometry and Integral Field Spectroscopy of the Young Brown Dwarf Companion to HD 1160. \apj, 834(2), 162.
• Garcia, E., Currie, T., Guyon, O., Stassun, K., Jovanovic, N., Lozi, J., Kudo, T., Doughty, D., Schlieder, J., Kwon, J., Uyama, T., Kuzuhara, M., Carson, J., Nakagawa, T., Hashimoto, J., Kusakabe, N., Abe, L., Brandner, W., Brandt, T., , Feldt, M., et al. (2017). "SCExAO and GPI Y JHBand Photometry and Integral Field Spectroscopy of the Young Brown Dwarf Companion to HD 1160". apj, 834, 162.
• Guyon, O. (2017). Habitable exoplanets detection: overview of challenges and current state-of-the-art [Invited]. Optics Express, 25(23), 28825.
• Guyon, O., & Males, J. (2017). "Adaptive Optics Predictive Control with Empirical Orthogonal Functions (EOFs)". ArXiv e-prints.
• Guyon, O., & Males, J. (2017). Adaptive Optics Predictive Control with Empirical Orthogonal Functions (EOFs). arXiv e-prints, arXiv:1707.00570.
• Guyon, O., Miller, K., Males, J., Belikov, R., & Kern, B. (2017). "Spectral Linear Dark Field Control: Stabilizing Deep Contrast for Exoplanet Imaging Using out-of-band Speckle Field". ArXiv e-prints.
• Guyon, O., Miller, K., Males, J., Belikov, R., & Kern, B. (2017). Spectral Linear Dark Field Control: Stabilizing Deep Contrast for Exoplanet Imaging Using out-of-band Speckle Field. arXiv e-prints, arXiv:1706.07377.
• Jovanovic, N., Cvetojevic, N., Norris, B., Betters, C., Schwab, C., Lozi, J., Guyon, O., Gross, S., Martinache, F., Tuthill, P., Doughty, D., Minowa, Y., Takato, N., & Lawrence, J. (2017). "Demonstration of an efficient, photonic-based astronomical spectrograph on an 8-m telescope". Optics Express, 25, 17753.
• Jovanovic, N., Guyon, O., Kawahara, H., & Kotani, T. (2017). "Application of Multicore Optical Fibers in Astronomy". ArXiv e-prints.
• Jovanovic, N., Guyon, O., Kawahara, H., & Kotani, T. (2017). Application of Multicore Optical Fibers in Astronomy. arXiv e-prints, arXiv:1704.01274.
• Jovanovic, N., Guyon, O., Kotani, T., Kawahara, H., Hosokawa, K., Lozi, J., Males, J., Ireland, M., Tamura, M., Mawet, D., Schwab, C., Norris, B., Leon-Saval, S. .., Betters, C., & Tuthill, P. (2017). "Developing post-coronagraphic, high-resolution spectroscopy for terrestrial planet characterization on ELTs". ArXiv e-prints.
• Jovanovic, N., Guyon, O., Kotani, T., Kawahara, H., Hosokawa, K., Lozi, J., Males, J., Ireland, M., Tamura, M., Mawet, D., Schwab, C., Norris, B., Leon-Saval, S. .., Betters, C., & Tuthill, P. (2017). Developing post-coronagraphic, high-resolution spectroscopy for terrestrial planet characterization on ELTs. arXiv e-prints, arXiv:1712.07762.
• Jovanovic, N., Guyon, O., Lozi, J., Tamura, M., Norris, B., Tuthill, P., Huby, E., Perrin, G., Lacour, S., Marchis, F., Duchene, G., Gauchet, L., Ireland, M., Feger, T., Rains, A., Bento, J., Schwab, C., Coutts, D., Cvetojevic, N., , Gross, S., et al. (2017). "Pioneering high contrast science instruments for planet characterization on giant segmented mirror telescopes". ArXiv e-prints.
• Jovanovic, N., Guyon, O., Lozi, J., Tamura, M., Norris, B., Tuthill, P., Huby, E., Perrin, G., Lacour, S., Marchis, F., Duchene, G., Gauchet, L., Ireland, M., Feger, T., Rains, A., Bento, J., Schwab, C., Coutts, D., Cvetojevic, N., , Gross, S., et al. (2017). Pioneering high contrast science instruments for planet characterization on giant segmented mirror telescopes. arXiv e-prints, arXiv:1712.08584.
• Jovanovic, N., Schwab, C., Guyon, O., Lozi, J., Cvetojevic, N., Martinache, F., Leon-Saval, S. .., Norris, B., Gross, S., Doughty, D., Currie, T., & Takato, N. (2017). "Efficient injection from large telescopes into single-mode fibres: Enabling the era of ultra-precision astronomy". aap, 604, A122.
• Kasper, M., Arsenault, R., K{"aufl}, H., Jakob, G., Fuenteseca, E., Riquelme, M., Siebenmorgen, R., Sterzik, M., Zins, G., Ageorges, N., Gutruf, S., Reutlinger, A., Kampf, D., Absil, O., Carlomagno, B., Guyon, O., Klupar, P., Mawet, D., Ruane, G., , Karlsson, M., et al. (2017). "NEAR: Low-mass Planets in {$alpha$ Cen with VISIR}". The Messenger, 169, 16-20.
• Kooistra, R., Kamp, I., Fukagawa, M., M{'enard}, F., Momose, M., Tsukagoshi, T., Kudo, T., Kusakabe, N., Hashimoto, J., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2017). "Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255". aap, 597, A132.
• Males, J., & Guyon, O. (2017). "Ground-based adaptive optics coronagraphic performance under closed-loop predictive control". ArXiv e-prints.
• Meyer, M., Quanz, S., Kasper, M., Guyon, O., & Monnier, J. (2017). "Blazing a Trail: Towards Imaging Super-Earths from the Ground and Space". LPI Contributions, 2042, 4108.
• Miller, K., Guyon, O., & Males, J. (2017). "Spatial linear dark field control: stabilizing deep contrast for exoplanet imaging using bright speckles". Journal of Astronomical Telescopes, Instruments, and Systems, 3(4), 049002.
• Rich, E. A., Wisniewski, J. P., McElwain, M. W., Hashimoto, J., Kudo, T., Kusakabe, N., Okamoto, Y. K., Abe, L., Akiyama, E., Brandner, W., Brandt, T. D., Cargile, P., Carson, J. C., Currie, T. M., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C. A., , Guyon, O., et al. (2017). The fundamental stellar parameters of FGK stars in the SEEDS survey Norman, OK 73071, USA. \mnras, 472(2), 1736-1752.
• Rich, E., Wisniewski, J., McElwain, M., Hashimoto, J., Kudo, T., Kusakabe, N., Okamoto, Y., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Cargile, P., Carson, J., Currie, T., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C., , Guyon, O., et al. (2017). "The fundamental stellar parameters of FGK stars in the SEEDS survey Norman, OK 73071, USA". mnras, 472, 1736-1752.
• Singh, G., Lozi, J., Jovanovic, N., Guyon, O., Baudoz, P., Martinache, F., & Kudo, T. (2017). "A Demonstration of a Versatile Low-order Wavefront Sensor Tested on Multiple Coronographs". pasp, 129(9), 095002.
• Uyama, T., Hashimoto, J., Kuzuhara, M., Mayama, S., Akiyama, E., Currie, T., Livingston, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T. D., Carson, J. C., Egner, S., Feldt, M., Goto, M., Grady, C. A., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2017). The SEEDS High-Contrast Imaging Survey of Exoplanets Around Young Stellar Objects. \aj, 153(3), 106.
• Uyama, T., Hashimoto, J., Kuzuhara, M., Mayama, S., Akiyama, E., Currie, T., Livingston, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2017). "The SEEDS High-Contrast Imaging Survey of Exoplanets Around Young Stellar Objects". aj, 153, 106.
• Yang, Y. i., Hashimoto, J., Hayashi, S. S., Tamura, M., Mayama, S., Rafikov, R., Akiyama, E., Carson, J. C., Janson, M., Kwon, J., Leon, J., Oh, D., Takami, M., Tang, Y., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T. D., , Egner, S., et al. (2017). Near-infrared Imaging Polarimetry of Inner Region of GG Tau A Disk. \aj, 153(1), 7.
• Yang, Y., Hashimoto, J., Hayashi, S., Tamura, M., Mayama, S., Rafikov, R., Akiyama, E., Carson, J., Janson, M., Kwon, J., Leon, J., Oh, D., Takami, M., Tang, Y., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T., , Egner, S., et al. (2017). "Near-infrared Imaging Polarimetry of Inner Region of GG Tau A Disk". aj, 153, 7.
• , F. M., , N. J., & , O. G. (2016). Closed-loop focal plane wavefront control with the SCExAO instrument. A&A.
  More info

  This article describes the implementation of a focal plane based wavefrontcontrol loop on the high-contrast imaging instrument SCExAO (SubaruCoronagraphic Extreme Adaptive Optics). The sensor relies on the Fourieranalysis of conventional focal-plane images acquired after an asymmetric maskis introduced in the pupil of the instrument. This absolute sensor is used herein a closed-loop to compensate the non-common path errors that normally affectsany imaging system relying on an upstream adaptive optics system.This specificimplementation was used to control low order modes corresponding to eightzernike modes (from focus to spherical). This loop was successfully run on-skyat the Subaru Telescope and is used to offset the SCExAO deformable mirrorshape used as a zero-point by the high-order wavefront sensor. The paperprecises the range of errors this wavefront sensing approach can operate withinand explores the impact of saturation of the data and how it can be bypassed,at a cost in performance. Beyond this application, because of its low hardwareimpact, APF-WFS can easily be ported in a wide variety of wavefront sensingcontexts, for ground- as well space-borne telescopes, and for telescope pupilsthat can be continuous, segmented or even sparse. The technique is powerfulbecause it measures the wavefront where it really matters, at the level of thescience detector.[Journal_ref: A&A 593, A33 (2016)]
• Akiyama, E., Hashimoto, J., Liu, H. B., Li, J. I., Bonnefoy, M., Dong, R., Hasegawa, Y., Henning, T., Sitko, M. L., Janson, M., Feldt, M., Wisniewski, J., Kudo, T., Kusakabe, N., Tsukagoshi, T., Momose, M., Muto, T., Taki, T., Kuzuhara, M., , Satoshi, M., et al. (2016). Spiral Structure and Differential Dust Size Distribution in the LKH\ensuremath{\alpha} 330 Disk. \aj, 152(6), 222.
• Asensio-Torres, R. .., Janson, M., Hashimoto, J., Thalmann, C., Currie, T., Buenzli, E., Kudo, T., Kuzuhara, M., Kusakabe, N., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., , Hayano, Y., et al. (2016). Polarimetry and flux distribution in the debris disk around HD 32297. \aap, 593, A73.
• Guyon, O., & Tamura, M. (2016). Special Section Guest Editorial:WFIRST-AFTA Coronagraphs. Journal of Astronomical Telescopes, Instruments, and Systems, 2, 010901.
• He{\lminiak}, K., Kuzuhara, M., Mede, K., Brandt, T., Kandori, R., Suenaga, T., Kusakabe, N., Narita, N., Carson, J., Currie, T., Kudo, T., Hashimoto, J., Abe, L., Akiyama, E., Brandner, W., Feldt, M., Goto, M., Grady, C., Guyon, O., , Hayano, Y., et al. (2016). SEEDS Direct Imaging of the RV-detected Companion to V450 Andromedae, and Characterization of the System. \apj, 832(1), 33.
• Jovanovic, N., Schwab, C., Cvetojevic, N., Guyon, O., & Martinache, F. (2016). "Enhancing Stellar Spectroscopy with Extreme Adaptive Optics and Photonics". pasp, 128(12), 121001.
• Jovanovic, N., Schwab, C., Cvetojevic, N., Guyon, O., & Martinache, F. (2016). Enhancing Stellar Spectroscopy with Extreme Adaptive Optics and Photonics. \pasp, 128(970), 121001.
• Kern, B., Guyon, O., Belikov, R., Wilson, D., Muller, R., Sidick, E., Balasubramanian, B., Krist, J., Poberezhskiy, I., & Tang, H. (2016). "Phase-induced amplitude apodization complex mask coronagraph mask fabrication, characterization, and modeling for WFIRST-AFTA". Journal of Astronomical Telescopes, Instruments, and Systems, 2(1), 011014.
• Konishi, M., Matsuo, T., Yamamoto, K., Samland, M., Sudo, J., Shibai, H., Itoh, Y., Fukagawa, M., Sumi, T., Kudo, T., Hashimoto, J., Kuzuhara, M., Kusakabe, N., Abe, L., Akiyama, E., Brandner, W., Brandt, T. D., Carson, J. C., Feldt, M., , Goto, M., et al. (2016). A substellar companion to Pleiades HII 3441. \pasj, 68(6), 92.
• Lomax, J. R., Wisniewski, J. P., Grady, C. A., McElwain, M. W., Hashimoto, J., Kudo, T., Kusakabe, N., Okamoto, Y. K., Fukagawa, M., Abe, L., Brandner, W., Brandt, T. D., Carson, J. C., Currie, T. M., Egner, S., Feldt, M., Goto, M., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2016). Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System. \apj, 828(1), 2.
• Martinache, F., Jovanovic, N., & Guyon, O. (2016). "Closed-loop focal plane wavefront control with the SCExAO instrument". aap, 593, A33.
• Mizuki, T., Yamada, T., Carson, J., Kuzuhara, M., Nakagawa, T., Nishikawa, J., Sitko, M., Kudo, T., Kusakabe, N., Hashimoto, J., Abe, L., Brander, W., Brandt, T., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2016). High-contrast imaging of ɛ Eridani with ground-based instruments. \aap, 595, A79.
• Newman, K., Conway, J., Belikov, R., & Guyon, O. (2016). "Focal Plane Phase Masks for PIAA: Design and Manufacturing". pasp, 128(5), 055003.
• Newman, K., Conway, J., Belikov, R., & Guyon, O. (2016). Focal Plane Phase Masks for PIAA: Design and Manufacturing. \pasp, 128(963), 055003.
• Noecker, M. C., Zhao, F., Demers, R., Trauger, J., Guyon, O., & Jeremy Kasdin, N. (2016). Coronagraph instrument for WFIRST-AFTA. Journal of Astronomical Telescopes, Instruments, and Systems, 2, 011001.
• Noecker, M., Zhao, F., Demers, R., Trauger, J., Guyon, O., & Jeremy Kasdin, N. (2016). "Coronagraph instrument for WFIRST-AFTA". Journal of Astronomical Telescopes, Instruments, and Systems, 2(1), 011001.
• Oh, D., Hashimoto, J., Carson, J. C., Janson, M., Kwon, J., Nakagawa, T., Mayama, S., Uyama, T., Yang, Y. i., Kudo, T., Kusakabe, N., Abe, L., Akiyama, E., Brandner, W., Brandt, T. D., Currie, T., Feldt, M., Goto, M., Grady, C. A., , Guyon, O., et al. (2016). Resolved Near-infrared Image of the Inner Cavity in the GM Aur Transitional Disk. \apjl, 831(1), L7.
• Oh, D., Hashimoto, J., Tamura, M., Wisniewski, J., Akiyama, E., Currie, T., Mayama, S., Takami, M., Thalmann, C., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Brandt, T. D., Carson, J. C., Egner, S., Feldt, M., Goto, M., Grady, C. A., , Guyon, O., et al. (2016). Near-infrared imaging polarimetry of LkCa 15: A possible warped inner disk$^{\textdagger}$. \pasj, 68(2), L3.
• Ohta, Y., Fukagawa, M., Sitko, M. L., Muto, T., Kraus, S., Grady, C. A., Wisniewski, J. P., Swearingen, J. R., Shibai, H., Sumi, T., Hashimoto, J., Kudo, T., Kusakabe, N., Momose, M., Okamoto, Y., Kotani, T., Takami, M., Currie, T., Thalmann, C., , Janson, M., et al. (2016). Extreme asymmetry in the polarized disk of V1247 Orionis*. \pasj, 68(4), 53.
• Pathak, P., Guyon, O., Jovanovic, N., Lozi, J., Martinache, F., Minowa, Y., Kudo, T., Takami, H., Hayano, Y., & Narita, N. (2016). "A High-precision Technique to Correct for Residual Atmospheric Dispersion in High-contrast Imaging Systems". pasp, 128(12), 124404.
• Pathak, P., Guyon, O., Jovanovic, N., Lozi, J., Martinache, F., Minowa, Y., Kudo, T., Takami, H., Hayano, Y., & Narita, N. (2016). A High-precision Technique to Correct for Residual Atmospheric Dispersion in High-contrast Imaging Systems. \pasp, 128(970), 124404.
• Pluzhnik, E., Guyon, O., Belikov, R., & Bendek, E. (2016). "Design of off-axis mirrors for the phase-induced amplitude apodization complex mask coronagraph". Journal of Astronomical Telescopes, Instruments, and Systems, 2(1), 011018.
• Ryu, T., Sato, B., Kuzuhara, M., Narita, N., Takahashi, Y. H., Uyama, T., Kudo, T., Kusakabe, N., Hashimoto, J., Omiya, M., Harakawa, H., Abe, L., Ando, H., Brandner, W., Brandt, T. D., Carson, J. C., Currie, T., Egner, S., Feldt, M., , Goto, M., et al. (2016). High-contrast Imaging of Intermediate-mass Giants with Long-term Radial Velocity Trends. \apj, 825(2), 127.
• Sirbu, D., Thomas, S. J., Belikov, R., Lozi, J., Bendek, E., Pluzhnik, E., Lynch, D. H., Hix, T., Zell, P., Guyon, O., & Schneider, G. (2016). Demonstration of broadband contrast at 1.2\ensuremath{\lambda}/D and greater for the EXCEDE starlight suppression system. Journal of Astronomical Telescopes, Instruments, and Systems, 2, 025002.
• Sirbu, D., Thomas, S. J., Belikov, R., Lozi, J., Bendek, E., Pluzhnik, E., Lynch, D. H., Hix, T., Zell, P., Guyon, O., & Schneider, G. (2016). Demonstration of broadband contrast at 1.2λ/D and greater for the EXCEDE starlight suppression system. Journal of Astronomical Telescopes, Instruments, and Systems, 2(2), 025002-1 - 025002-14. doi:10.1117/1.JATIS.2.2.025002
• Traub, W., Breckinridge, J., Greene, T., Guyon, O., Jeremy Kasdin, N., & Macintosh, B. (2016). "Science yield estimate with the Wide-Field Infrared Survey Telescope coronagraph". Journal of Astronomical Telescopes, Instruments, and Systems, 2(1), 011020.
• Akiyama, E., Muto, T., Kusakabe, N., Kataoka, A., Hashimoto, J., Tsukagoshi, T., Kwon, J., Kudo, T., Kandori, R., Grady, C., Takami, M., Janson, M., Kuzuhara, M., Henning, T., Sitko, M., Carson, J., Mayama, S., Currie, T., Thalmann, C., , Wisniewski, J., et al. (2015). Discovery of a Disk Gap Candidate at 20 AU in TW Hydrae. \apjl, 802(2), L17.
• Dalcanton, J., Seager, S., Aigrain, S., Battel, S., Brandt, N., Conroy, C., Feinberg, L., Gezari, S., Guyon, O., Harris, W., Hirata, C., Mather, J., Postman, M., Redding, D., Schiminovich, D., Stahl, H. P., & Tumlinson, J. (2015). From Cosmic Birth to Living Earths: The Future of UVOIR Space Astronomy. arXiv e-prints, arXiv:1507.04779.
• Follette, K. B., Grady, C. A., Swearingen, J. R., Sitko, M. L., Champney, E. H., Marel, N., Takami, M., Kuchner, M. J., Close, L. M., Muto, T., Mayama, S., McElwain, M. W., Fukagawa, M., Maaskant, K., Min, M., Russell, R. W., Kudo, T., Kusakabe, N., Hashimoto, J., , Abe, L., et al. (2015). SEEDS Adaptive Optics Imaging of the Asymmetric Transition Disk Oph IRS 48 in Scattered Light. \apj, 798(2), 132.
• Grady, C., Fukagawa, M., Maruta, Y., Ohta, Y., Wisniewski, J., Hashimoto, J., Okamoto, Y., Momose, M., Currie, T., McElwain, M., Muto, T., Kotani, T., Kusakabe, N., Feldt, M., Sitko, M., Follette, K., Bonnefoy, M., Henning, T., Takami, M., , Karr, J., et al. (2015). The outer disks of Herbig stars from the UV to NIR. \apss, 355(2), 253-266.
• Hashimoto, J., Tsukagoshi, T., Brown, J., Dong, R., Muto, T., Zhu, Z., Wisniewski, J., Ohashi, N., kudo, T., Kusakabe, N., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Carson, J., Currie, T., Egner, S., Feldt, M., Grady, C., , Guyon, O., et al. (2015). The Structure of Pre-transitional Protoplanetary Disks. II. Azimuthal Asymmetries, Different Radial Distributions of Large and Small Dust Grains in PDS 70. \apj, 799(1), 43.
• Jovanovic, N., Guyon, O., Martinache, F., Pathak, P., Hagelberg, J., & Kudo, T. (2015). Artificial Incoherent Speckles Enable Precision Astrometry and Photometry in High-contrast Imaging. \apjl, 813(2), L24.
• Jovanovic, N., Martinache, F., Guyon, O., Clergeon, C., Singh, G., Kudo, T., Garrel, V., Newman, K., Doughty, D., Lozi, J., Males, J., Minowa, Y., Hayano, Y., Takato, N., Morino, J., Kuhn, J., Serabyn, E., Norris, B., Tuthill, P., , Schworer, G., et al. (2015). The Subaru Coronagraphic Extreme Adaptive Optics System: Enabling High-Contrast Imaging on Solar-System Scales. \pasp, 127(955), 890.
• Konishi, M., Shibai, H., Sumi, T., Fukagawa, M., Matsuo, T., Samland, M. S., Yamamoto, K., Sudo, J., Itoh, Y., Arimoto, N., Kajisawa, M., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Currie, T., Egner, S. E., Feldt, M., Goto, M., , Grady, C. A., et al. (2015). Indications of M-dwarf deficits in the halo and thick disk of the Galaxy. \pasj, 67(1), 1.
• Leon, J., Takami, M., Karr, J. L., Hashimoto, J., Kudo, T., Sitko, M., Mayama, S., Kusakabe, N., Akiyama, E., Liu, H. B., Usuda, T., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Currie, T., Egner, S. E., Feldt, M., Follette, K., , Grady, C. A., et al. (2015). Near-IR High-resolution Imaging Polarimetry of the SU Aur Disk: Clues for Tidal Tails?. \apjl, 806(1), L10.
• Momose, M., Morita, A., Fukagawa, M., Muto, T., Takeuchi, T., Hashimoto, J., Honda, M., Kudo, T., Okamoto, Y. K., Kanagawa, K. D., Tanaka, H., Grady, C. A., Sitko, M. L., Akiyama, E., Currie, T., Follette, K. B., Mayama, S., Kusakabe, N., Abe, L., , Brandner, W., et al. (2015). Detailed structure of the outer disk around HD 169142 with polarized light in H-band. \pasj, 67(5), 83.
• Newman, K., Guyon, O., Balasubramanian, K., Belikov, R., Jovanovic, N., Martinache, F., & Wilson, D. (2015). An Achromatic Focal Plane Mask for High-Performance Broadband Coronagraphy. \pasp, 127(951), 437.
• Norris, B., Schworer, G., Tuthill, P., Jovanovic, N., Guyon, O., Stewart, P., & Martinache, F. (2015). The VAMPIRES instrument: imaging the innermost regions of protoplanetary discs with polarimetric interferometry. \mnras, 447(3), 2894-2906.
• Rich, E. A., Wisniewski, J. P., Mayama, S., Brandt, T. D., Hashimoto, J., Kudo, T., Kusakabe, N., Espaillat, C., Abe, L., Akiyama, E., Brandner, W., Carson, J. C., Currie, T., Egner, S., Feldt, M., Follette, K., Goto, M., Grady, C. A., Guyon, O., , Hayano, Y., et al. (2015). Near-IR Polarized Scattered Light Imagery of the DoAr 28 Transitional Disk. \aj, 150(3), 86.
• Singh, G., Lozi, J., Guyon, O., Baudoz, P., Jovanovic, N., Martinache, F., Kudo, T., Serabyn, E., & Kuhn, J. (2015). On-Sky Demonstration of Low-Order Wavefront Sensing and Control with Focal Plane Phase Mask Coronagraphs. \pasp, 127(955), 857.
• Spergel, D., Gehrels, N., Baltay, C., Bennett, D., Breckinridge, J., Donahue, M., Dressler, A., Gaudi, B., Greene, T., Guyon, O., Hirata, C., Kalirai, J., Kasdin, N., Macintosh, B., Moos, W., Perlmutter, S., Postman, M., Rauscher, B., Rhodes, J., , Wang, Y., et al. (2015). Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report. arXiv e-prints, arXiv:1503.03757.
• Bonnefoy, M., Currie, T., Marleau, G. -., Schlieder, J., Wisniewski, J., Carson, J., Covey, K., Henning, T., Biller, B., Hinz, P., Klahr, H., Marsh, B. A., Zimmerman, N., Janson, M., McElwain, M., Mordasini, C., Skemer, A., Bailey, V., Defr{\`ere}, D., , Thalmann, C., et al. (2014). Characterization of the gaseous companion \ensuremath{\kappa} Andromedae b. New Keck and LBTI high-contrast observations. \aap, 562, A111.
• Brandt, T. D., Kuzuhara, M., McElwain, M. W., Schlieder, J. E., Wisniewski, J. P., Turner, E. L., Carson, J., Matsuo, T., Biller, B., Bonnefoy, M., Dressing, C., Janson, M., Knapp, G., Moro-Mart{\'\in}, A., Thalmann, C., Kudo, T., Kusakabe, N., Hashimoto, J., Abe, L., , Brandner, W., et al. (2014). The Moving Group Targets of the SEEDS High-contrast Imaging Survey of Exoplanets and Disks: Results and Observations from the First Three Years. \apj, 786(1), 1.
• Brandt, T. D., McElwain, M. W., Turner, E. L., Mede, K., Spiegel, D. S., Kuzuhara, M., Schlieder, J. E., Wisniewski, J. P., Abe, L., Biller, B., Brandner, W., Carson, J., Currie, T., Egner, S., Feldt, M., Golota, T., Goto, M., Grady, C., Guyon, O., , Hashimoto, J., et al. (2014). A Statistical Analysis of SEEDS and Other High-contrast Exoplanet Surveys: Massive Planets or Low-mass Brown Dwarfs?. \apj, 794(2), 159.
• Currie, T., Guyon, O., Martinache, F., Clergeon, C., McElwain, M., Thalmann, C., Jovanovic, N., Singh, G., & Kudo, T. (2014). SCExAO: First results and on-sky performance. Proceedings of the International Astronomical Union, 8(S299), 34-35.
  More info

  Abstract: We present new on-sky results for the Subaru Coronagraphic Extreme Adaptive Optics imager (SCExAO) verifying and quantifying the contrast gain enabled by key components: the closed-loop coronagraphic low-order wavefront sensor (CLOWFS) and focal plane wavefront control ("speckle nulling"). SCExAO will soon be coupled with a high-order, Pyramid wavefront sensor which will yield > 90% Strehl ratio and enable 106-107 contrast at small angular separations allowing us to image gas giant planets at solar system scales. Upcoming instruments like VAMPIRES, FIRST, and CHARIS will expand SCExAO's science capabilities. Copyright © 2013, International Astronomical Union.
• Guyon, O., Hinz, P. M., Cady, E., Belikov, R., & Martinache, F. (2014). High Performance Lyot and PIAA Coronagraphy for Arbitrarily Shaped Telescope Apertures. \apj, 780(2), 171.
• Itoh, Y., Oasa, Y., Kudo, T., Kusakabe, N., Hashimoto, J., Abe, L., Brandner, W., Brandt, T. D., Carson, J. C., Egner, S., Feldt, M., Grady, C. A., Guyon, O., Hayano, Y., Hayashi, M., Hayashi, S. S., Henning, T., Hodapp, K. W., Ishii, M., , Iye, M., et al. (2014). Near-infrared polarimetry of the GG Tauri A binary system. Research in Astronomy and Astrophysics, 14(11), 1438-1446.
• Kouveliotou, C., Agol, E., Batalha, N., Bean, J., Bentz, M., Cornish, N., Dressler, A., Figueroa-Feliciano, E. .., Gaudi, S., Guyon, O., Hartmann, D., Kalirai, J., Niemack, M., Ozel, F., Reynolds, C., Roberge, A., Straughn, K., Weinberg, D., & Zmuidzinas, J. (2014). Enduring Quests-Daring Visions (NASA Astrophysics in the Next Three Decades). arXiv e-prints, arXiv:1401.3741.
• Martinache, F., Guyon, O., Jovanovic, N., Clergeon, C., Singh, G., Kudo, T., Currie, T., Thalmann, C., McElwain, M., & Tamura, M. (2014). On-Sky Speckle Nulling Demonstration at Small Angular Separation with SCExAO. \pasp, 126(940), 565.
• Norris, B., Tuthill, P., Jovanovic, N., Schworer, G., Guyon, O., Stewart, P., & Martinache, F. (2014). The VAMPIRES instrument: Imaging the innermost regions of protoplanetary disks with polarimetric interferometry. arXiv e-prints, arXiv:1405.7426.
• Oshiyama, F., Murakami, N., Guyon, O., Martinache, F., Baba, N., Matsuo, T., Nishikawa, J., & Tamura, M. (2014). Central-Obscuration Removal Plates for Focal-Plane Phase-Mask Coronagraphs with a Centrally-Obscured Telescope. \pasp, 126(937), 270.
• Oshiyama, F., Murakami, N., Guyon, O., Martinache, F., Baba, N., Matsuo, T., Nishikawa, J., & Tamura, M. (2014). Central-obscuration removal plates for focal-plane phase-mask coronagraphs with a centrally-obscured telescope. Publications of the Astronomical Society of the Pacific, 126(937), 270-279.
  More info

  Abstract: Focal-plane phase-mask coronagraphs, such as eight-octant phase-mask coronagraphs (8OPM), are one of the most promising tools for high contrast observations. However, coronagraphic performance would be degraded when combined with a centrally-obscured telescope. We propose pupil-remapping optics for removing the shade of a secondary mirror to generate a clear, circular pupil for the phase-mask coronagraph. First, we show the design of the pupil-remapping optics, called central-obscuration removal plates (CRPs). Next, we report laboratory experiments on the 8OPM coronagraph using manufactured CRPs. We also evaluate off-axis point-spread functions via both laboratory experiments and numerical simulations. Finally, we evaluate, via numerical simulations, limiting factors for coronagraphic performance, such as phase aberrations introduced by the CRPs, the effect of Fresnel diffraction, and chromatic behavior. The numerical simulations suggest that the phase aberrations could be a dominant limiting factor of the achievable contrast in the current laboratory experiments. © 2014. The Astronomical Society of the Pacific. All rights reserved.
• Singh, G., Martinache, F., Baudoz, P., Guyon, O., Matsuo, T., Jovanovic, N., & Clergeon, C. (2014). Lyot-based Low Order Wavefront Sensor for Phase-mask Coronagraphs: Principle, Simulations and Laboratory Experiments. \pasp, 126(940), 586.
• Takami, M., Hasegawa, Y., Muto, T., Gu, P., Dong, R., Karr, J. L., Hashimoto, J., Kusakabe, N., Chapillon, E., Tang, Y., Itoh, Y., Carson, J., Follette, K. B., Mayama, S., Sitko, M., Janson, M., Grady, C. A., Kudo, T., Akiyama, E., , Kwon, J., et al. (2014). Surface Geometry of Protoplanetary Disks Inferred From Near-Infrared Imaging Polarimetry. \apj, 795(1), 71.
• Tsukagoshi, T., Momose, M., Hashimoto, J., Kudo, T., Andrews, S., Saito, M., Kitamura, Y., Ohashi, N., Wilner, D., Kawabe, R., Abe, L., Akiyama, E., Brandner, W., Brandt, T. D., Carson, J., Currie, T., Egner, S. E., Goto, M., Grady, C., , Guyon, O., et al. (2014). High-resolution Submillimeter and Near-infrared Studies of the Transition Disk around Sz 91. \apj, 783(2), 90.
• Balasubramanian, K., Wilson, D., White, V., Muller, R., Dickie, M., Yee, K., Ruiz, R., Shaklan, S., Cady, E., Kern, B., Belikov, R., Guyon, O., & Kasdin, N. J. (2013). High contrast internal and external coronagraph masks produced by various techniques. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: High contrast internal and external coronagraphic imaging requires a variety of masks depending on different architectures to suppress star light. Various fabrication technologies are required to address a wide range of needs including gradient amplitude transmission, tunable phase profiles, ultra-low reflectivity, precise small scale features, and low-chromaticity. We present the approaches employed at JPL to produce pupil plane and image plane coronagraph masks, and lab-scale external occulter type masks by various techniques including electron beam, ion beam, deep reactive ion etching, and black silicon technologies with illustrative examples of each. Further development is in progress to produce circular masks of various kinds for obscured aperture telescopes. © 2013 SPIE.
• Belikov, R., Bendek, E., Greene, T. P., Guyon, O., Lozi, J., Lynch, D. H., Newman, K. E., Pluzhnik, E., Schneider, G., Tenerelli, D., Thomas, S. J., & Witteborn, F. C. (2013). EXCEDE Technology Development II: Demonstration of High Contrast at 1.2 λ/D and Preliminary Broadband Results.. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: Coronagraph technology is advancing and promises to enable space telescopes capable of directly detecting low surface brightness circumstellar debris disks as well as giant planets as close as in the habitable zones of their host stars. One mission capable of doing this is called EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer), which in 2011 was selected by NASA's Explorer program for technology development (Category III). EXCEDE is a 0.7m space telescope concept designed to achieve raw contrasts of 10 -6 at an inner working angle of 1.2 λ/D and 10-7 at 2 λ/D and beyond. In addition to doing fundamental science on debris disks, EXCEDE will also serve as a technological and scientific precursor for an exo-Earth imaging mission. EXCEDE uses a Starlight Suppression System (SSS) based on the Phase Induced Amplitude Apodization (PIAA) coronagraph to provide high throughput and high contrast close to the diffraction limit, enabling aggressive performance. We report on our continuing progress of developing the SSS for EXCEDE, including (a) high contrast performance demonstrations at 1.2 λ/D, which includes a lab demonstration of 2×10-7 median contrast between 1.2 and 2.0 λ/D simultaneously with 6.5×10 -8 median contrast between 2 and 4 λ/D in monochromatic light at 655nm, meeting a major milestone in our technology development program; (b) the installation of a new Low Order Wavefront Sensor (LOWFS) which enabled achieving deep contrasts at aggressive inner working angles; (c) implementation of more efficient model-based wavefront control algorithms; and (d) a preliminary broadband contrast result of 6×10-6 contrast at 1.2 λ/D in a 10% band. © 2013 SPIE.
• Bendek, E. A., Guyon, O., Ammons, S. M., & Belikov, R. (2013). Laboratory Demonstration of Astrometric Compensation Using a Diffractive Pupil. \pasp, 125(932), 1212.
• Bendek, E. A., Guyon, O., Ammons, S. M., & Belikov, R. (2013). Laboratory demonstration of astrometric compensation using a diffractive pupil. Publications of the Astronomical Society of the Pacific, 125(932), 1212-1225.
  More info

  Abstract: Astrometry is a promising exoplanet detection and characterization technique that can detect earthsize exoplanets if submicroarcsecond precision is achieved. However, instrumentation available today can only reach in the order of 102 microarcseconds, mainly limited by long-term dynamic distortions on wide-field observations. To overcome this problem, we propose the implementation of a diffractive pupil, which has an array of microscopic dots imprinted on the primary mirror coating. The dots create diffractive spikes on the focal plane that are used to calibrate image plane distortions that degrade the astrometric measurement precision. This astrometry technique can be utilized simultaneously with coronagraphy for exhaustive characterization of exoplanets (mass, spectra, orbit). We designed and built an astrometry laboratory to validate the diffractive pupil ability to calibrate distortions and stabilize wide-field astrometric measurements over time. We achieved a precision of 0.0123 px, which represents 42% of the 0.0288 px stability measured for this setup before the calibration. On sky units, this result is equivalent to 3:42 × 10-3λ=D that corresponds to 150 μas for a 2.4 m telescope at 500 nm wavelength. Also, at large field angles the distortion error was reduced by a factor of 5 when the calibration was used, proving its effectiveness for large field of view.We present an astrometry error budget here to explain the source of the residual error observed when the diffractive pupil calibration is used. © 2013. The Astronomical Society of the Pacific. All rights reserved.
• Bendek, E. A., Guyon, O., Belikov, R., Ammons, S. M., Milster, T., Kim, Y., & Johnson, L. (2013). Exoplanet detection and characterization using combined coronagraphy and sub-uas astrometry from space. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: Combining high-contrast imaging and astrometry in a single space mission would enable efficient detection and characterization of single- and multiple-planetary systems around nearby stars, allowing determination of planetary mass, composition, atmosphere, and system architecture. These science goals can be achieved using a 2m wide-field (>0.1deg2) class telescope equipped with two instruments: a high-performance coronagraph to perform direct imaging, and a wide field camera to achieve sub-microarcsecond astrometric accuracy. However, these measurements are only possible if there are no relative distortion changes between astrometric observations. At sub-microarcsecond accuracy regime, even space optics suffers from dynamic distortions in the optical system and dominates the error budget. We propose to utilize a diffractive pupil, in which an array of dots on the primary mirror generates polychromatic diffraction spikes in the focal plane to calibrate the dynamic distortions of the optical system. According to simulations, this technique would allow to obtain 0.2 microarcsecond single-visit precision astrometric accuracy. In this paper we present the laboratory results that demonstrate the diffractive pupil concept on wide-field images. We also discuss simulations and experiments performed at the NASA Ames ACE test bed, demonstrating that the diffractive pupil does not affect the coronagraph performance down to 2×10-7. Finally, we assess the compatibility of a diffractive pupil telescope with a general astrophysics mission, showing that the spikes do not impact wide-field observations. © 2013 SPIE.
• Bendek, E., Belikov, R., Pluzhnik, E., & Guyon, O. (2013). Compatibility of a Diffractive Pupil and Coronagraphic Imaging. \pasp, 125(924), 204.
• Bendek, E., Belikov, R., Pluzhnik, E., & Guyon, O. (2013). Compatibility of a diffractive pupil and coronagraphic imaging. Publications of the Astronomical Society of the Pacific, 125(924), 204-212.
  More info

  Abstract: Detection and characterization of exo-Earths require direct imaging techniques that can deliver contrast ratios of 1010 at 100 mas or smaller angular separation. At the same time, astrometric data is required to measure planet masses and to help detect planets and constrain their orbital parameters. To minimize costs, a single space mission can be designed using a high-efficiency coronagraph to perform direct imaging and a diffractive pupil to calibrate wide field distortions to enable high-precision astrometric measurements. This article reports the testing of a diffractive pupil on the high-contrast test bed at the NASA Ames Research Center to assess the compatibility of using a diffractive pupil with coronagraphic imaging systems. No diffractive contamination was found within our detectability limit of 2 × 10-7 contrast outside a region of 12 λ=D and 2:5 × 10-6 within a region spanning from 2 to 12 λ=D. Morphology of the image features suggests that no contamination exists even beyond the detectability limit specified or at smaller working angles. In the case that diffractive contamination is found beyond these stated levels, active wavefront control would be able to mitigate its intensity to 10-7 or better contrast. © 2013. The Astronomical Society of the Pacific. All rights reserved.
• Brandt, T. D., McElwain, M. W., Turner, E. L., Abe, L., Brandner, W., Carson, J., Egner, S., Feldt, M., Golota, T., Goto, M., Grady, C. A., Guyon, O., Hashimoto, J., Hayano, Y., Hayashi, M., Hayashi, S., Henning, T., Hodapp, K. W., Ishii, M., , Iye, M., et al. (2013). New techniques for high-contrast imaging with ADI: The ACORNS-ADI seeds data reduction pipeline. Astrophysical Journal, 764(2).
  More info

  Abstract: We describe Algorithms for Calibration, Optimized Registration, and Nulling the Star in Angular Differential Imaging (ACORNS-ADI), a new, parallelized software package to reduce high-contrast imaging data, and its application to data from the SEEDS survey. We implement several new algorithms, including a method to register saturated images, a trimmed mean for combining an image sequence that reduces noise by up to ∼20%, and a robust and computationally fast method to compute the sensitivity of a high-contrast observation everywhere on the field of view without introducing artificial sources. We also include a description of image processing steps to remove electronic artifacts specific to Hawaii2-RG detectors like the one used for SEEDS, and a detailed analysis of the Locally Optimized Combination of Images (LOCI) algorithm commonly used to reduce high-contrast imaging data. ACORNS-ADI is written in python. It is efficient and open-source, and includes several optional features which may improve performance on data from other instruments. ACORNS-ADI requires minimal modification to reduce data from instruments other than HiCIAO. It is freely available for download at www.github.com/t-brandt/acorns-adi under a Berkeley Software Distribution (BSD) license. © 2013. The American Astronomical Society. All rights reserved.
• Brandt, T. D., McElwain, M. W., Turner, E. L., Abe, L., Brandner, W., Carson, J., Egner, S., Feldt, M., Golota, T., Goto, M., Grady, C., Guyon, O., Hashimoto, J., Hayano, Y., Hayashi, M., Hayashi, S., Henning, T., Hodapp, K., Ishii, M., , Iye, M., et al. (2013). New Techniques for High-contrast Imaging with ADI: The ACORNS-ADI SEEDS Data Reduction Pipeline. \apj, 764(2), 183.
• Carson, J., Thalmann, C., Janson, M., Kozakis, T., Bonnefoy, M., Biller, B., Schlieder, J., Currie, T., McElwain, M., Goto, M., Henning, T., Brandner, W., Feldt, M., Kandori, R., Kuzuhara, M., Stevens, L., Wong, P., Gainey, K., Fukagawa, M., , Kuwada, Y., et al. (2013). Direct Imaging Discovery of a ``Super-Jupiter'' around the Late B-type Star \ensuremath{\kappa} And. \apjl, 763(2), L32.
• Carson, J., Thalmann, C., Janson, M., Kozakis, T., Bonnefoy, M., Biller, B., Schlieder, J., Currie, T., McElwain, M., Goto, M., Henning, T., Brandner, W., Feldt, M., Kandori, R., Kuzuhara, M., Stevens, L., Wong, P., Gainey, K., Fukagawa, M., , Kuwada, Y., et al. (2013). Direct imaging discovery of a "sUPER-JUPITER" around the late b-type star κ and. Astrophysical Journal Letters, 763(2).
  More info

  Abstract: We present the direct imaging discovery of an extrasolar planet, or possible low-mass brown dwarf, at a projected separation of 55 ± 2 AU (1.″058 ± 0.″007) from the B9-type star κ And. The planet was detected with Subaru/HiCIAO during the SEEDS survey and confirmed as a bound companion via common proper motion measurements. Observed near-infrared magnitudes of J = 16.3 ± 0.3, H = 15.2 ± 0.2, K s = 14.6 ± 0.4, and L′ = 13.12 ± 0.09 indicate a temperature of ∼1700 K. The galactic kinematics of the host star are consistent with membership in the Columba Association, implying a corresponding age of 30 +20-10 Myr. The system's age, combined with the companion photometry, points to a model-dependent companion mass ∼12.8 M Jup. The host star's estimated mass of 2.4-2.5 M⊙ places it among the most massive stars ever known to harbor an extrasolar planet or low-mass brown dwarf. While the mass of the companion is close to the deuterium burning limit, its mass ratio, orbital separation, and likely planet-like formation scenario imply that it may be best defined as a "super-Jupiter" with properties similar to other recently discovered companions to massive stars. © 2013. The American Astronomical Society. All rights reserved.
• Currie, T., Guyon, O., Martinache, F., Clergeon, C., McElwain, M., Thalmann, C., Jovanovic, N., Singh, G., & Kudo, T. (2013). The Subaru Coronagraphic Extreme Adaptive Optics Imager: First Results and On-Sky Performance. arXiv e-prints, arXiv:1307.4093.
• Follette, K. B., Tamura, M., Hashimoto, J., Whitney, B., Grady, C., Close, L., Andrews, S. M., Kwon, J., Wisniewski, J., Brandt, T. D., Mayama, S., Kandori, R., Dong, R., Abe, L., Brandner, W., Carson, J., Currie, T., Egner, S. E., Feldt, M., , Goto, M., et al. (2013). Mapping H-band Scattered Light Emission in the Mysterious SR21 Transitional Disk. \apj, 767(1), 10.
• Grady, C. A., Muto, T., Hashimoto, J., Fukagawa, M., Currie, T., Biller, B., Thalmann, C., Sitko, M. L., Russell, R., Wisniewski, J., Dong, R., Kwon, J., Sai, S., Hornbeck, J., Schneider, G., Hines, D., Martín, A. M., Feldt, M., Henning, T., , Pott, J. -., et al. (2013). Spiral arms in the asymmetrically illuminated disk of MWC 758 and constraints on giant planets. Astrophysical Journal, 762(1).
  More info

  Abstract: We present the first near-IR scattered light detection of the transitional disk associated with the Herbig Ae star MWC 758 using data obtained as part of the Strategic Exploration of Exoplanets and Disks with Subaru, and 1.1 μm Hubble Space Telescope/NICMOS data. While submillimeter studies suggested there is a dust-depleted cavity with r = 0.″35, we find scattered light as close as 0.″1 (20-28 AU) from the star, with no visible cavity at H, K′, or Ks . We find two small-scaled spiral structures that asymmetrically shadow the outer disk. We model one of the spirals using spiral density wave theory, and derive a disk aspect ratio of h ∼ 0.18, indicating a dynamically warm disk. If the spiral pattern is excited by a perturber, we estimate its mass to be 5+3-4 MJ , in the range where planet filtration models predict accretion continuing onto the star. Using a combination of non-redundant aperture masking data at L′ and angular differential imaging with Locally Optimized Combination of Images at K′ and Ks , we exclude stellar or massive brown dwarf companions within 300 mas of the Herbig Ae star, and all but planetary mass companions exterior to 0.″5. We reach 5σ contrasts limiting companions to planetary masses, 3-4 MJ at 1.″0 and 2 M J at 1.″55, using the COND models. Collectively, these data strengthen the case for MWC 758 already being a young planetary system. © 2013. The American Astronomical Society. All rights reserved.
• Grady, C., Muto, T., Hashimoto, J., Fukagawa, M., Currie, T., Biller, B., Thalmann, C., Sitko, M., Russell, R., Wisniewski, J., Dong, R., Kwon, J., Sai, S., Hornbeck, J., Schneider, G., Hines, D., Moro, M. A., Feldt, M., Henning, T., , Pott, J. -., et al. (2013). Spiral Arms in the Asymmetrically Illuminated Disk of MWC 758 and Constraints on Giant Planets. \apj, 762(1), 48.
• Groff, T. D., Peters, M. A., Kasdin, N. J., Knapp, G., Galvin, M., Carr, M. A., McElwain, M. W., Brandt, T., Janson, M., Gunn, J. E., Lupton, R., Guyon, O., Martinache, F., Jovanovic, N., Hayashi, M., & Takato, N. (2013). Design of the CHARIS integral field spectrograph for exoplanet imaging. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: Princeton University is building an integral field spectrograph (IFS), the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), for integration with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system and the AO188 adaptive optics system on the Subaru telescope. CHARIS and SCExAO will measure spectra of hot, young Jovian planets in a coronagraphic image across J, H, and K bands down to an 80 milliarcsecond inner working angle. SCExAO's coronagraphs and wavefront control system will make it possible to detect companions five orders of magnitude dimmer than their parent star. However, quasi-static speckles in the image contaminate the signal from the planet. In an IFS this also causes uncertainty in the spectra due to diffractive cross-contamination, commonly referred to as crosstalk. Post-processing techniques can subtract these speckles, but they can potentially skew spectral measurements, become less effective at small angular separation, and at best can only reduce the crosstalk down to the photon noise limit of the contaminating signal. CHARIS will address crosstalk effects of a high contrast image through hardware design, which drives the optical and mechanical design of the assembly. The work presented here sheds light on the optical and mechanical considerations taken in designing the IFS to provide high signal-to-noise spectra in a coronagraphic image from and extreme adaptive optics image. The design considerations and lessons learned are directly applicable to future exoplanet instrumentation for extremely large telescopes and space observatories capable of detecting rocky planets in the habitable zone. © 2013 SPIE.
• Guyon, O. (2013). Imaging earth-like planets around late-type stars with low-inner working angle PIAA coronagraphy. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: Thanks to the use of aspheric optics for lossless apodization, the Phase Induced Amplitude Apodization (PIAA) coronagraph offers full throughput, high contrast and small inner working angle. It is therefore ideally suited for space-based direct imaging of potentially habitable exoplanets. The PIAA concept has recently evolved to a higher performance version, the PIAA complex mask coronagraph (PIAACMC), which uses a combination of phase and amplitude focal plane mask for improved inner working angle and higher contrast. In this paper, PIAACMC design for a telescope with a large central obstruction (of size similar to AFTA's pupil) is described. The potential to image and study potentially habitable planets with a 2.4m telescope is considered. A PIAACMC with a 1.3 λ/D inner working angle appears particularly suitable for the telescope, thanks to a design optimization reducing sensitivity to pointing errors and stellar angular size. © 2013 SPIE.
• Guyon, O., Eisner, J. A., Angel, R., Woolf, N. J., Bendek, E. A., Milster, T. D., Ammons, S. M., Shao, M., Shaklan, S., Levine, M., Nemati, B., Martinache, F., Pitman, J., Woodruff, R. A., & Belikov, R. (2013). Simultaneous Exoplanet Characterization and Deep Wide-field Imaging with a Diffractive Pupil Telescope. \apj, 767(1), 11.
• Guyon, O., Mennesson, B., Serabyn, E., & Martin, S. (2013). Optimal Beam Combiner Design for Nulling Interferometers. \pasp, 125(930), 951.
• Guyon, O., Mennesson, B., Serabyn, E., & Martin, S. (2013). Optimal beam combiner design for nulling interferometers. Publications of the Astronomical Society of the Pacific, 125(930), 951-965.
  More info

  Abstract: A scheme to optimally design a beam combiner is discussed for any predetermined fixed geometry nulling interferometer aimed at detection and characterization of exoplanets with multiple telescopes or a single telescope (aperture masking).We show that considerably higher order nulls can be achieved with 1D (one-dimensional) interferometer geometries than possible with 2D (two-dimensional) geometries with the same number of apertures. Any 1D interferometer with N apertures can achieve a 2{eth}N 1{Thorn}-order null, while the order of the deepest null for a random 2D aperture geometry interferometer is the order of the Nth term in the Taylor expansion of ei(x2+y2) around x = 0, y = 0 (2nd order null for N = 2; 3; 4th order null for N = 4; 5; 6).We also show that an optimal beam combiner for nulling interferometry relies on only 0 or π phase shifts. Examples of nulling interferometer designs are shown to illustrate these findings. © 2013. The Astronomical Society of the Pacific. All rights reserved.
• Hashimoto, J., Dong, R., Kudo, T., Honda, M., McClure, M. K., Zhu, Z., Muto, T., Wisniewski, J., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C. A., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2013). Erratum: Polarimetric imaging of large cavity structures in the pre-transitional protoplanetary disk around pds 70: Observations of the disk (Astrophysical Journal Letters (2012) 758 (L19)). Astrophysical Journal Letters, 775(1).
• Hashimoto, J., Dong, R., Kudo, T., Honda, M., McClure, M., Zhu, Z., Muto, T., Wisniewski, J., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2013). Erratum: ``Polarimetric Imaging of Large Cavity Structures in the Pre-transitional Protoplanetary Disk around PDS 70: Observations of the Disk'' (2012, ApJL, 758, L19). \apjl, 775(1), L33.
• Janson, M., Brandt, T. D., Kuzuhara, M., Spiegel, D. S., Thalmann, C., Currie, T., Bonnefoy, M., Zimmerman, N., Sorahana, S., Kotani, T., Schlieder, J., Hashimoto, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Carson, J. C., Egner, S., Feldt, M., , Goto, M., et al. (2013). Direct Imaging Detection of Methane in the Atmosphere of GJ 504 b. \apjl, 778(1), L4.
• Janson, M., Brandt, T. D., Kuzuhara, M., Spiegel, D. S., Thalmann, C., Currie, T., Bonnefoy, M., Zimmerman, N., Sorahana, S., Kotani, T., Schlieder, J., Hashimoto, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Carson, J. C., Egner, S., Feldt, M., , Goto, M., et al. (2013). Direct imaging detection of methane in the atmosphere of GJ 504 b. Astrophysical Journal Letters, 778(1).
  More info

  Abstract: Most exoplanets detected by direct imaging thus far have been characterized by relatively hot (≳1000 K) and cloudy atmospheres. A surprising feature in some of their atmospheres has been a distinct lack of methane, possibly implying non-equilibrium chemistry. Recently, we reported the discovery of a planetary companion to the Sun-like star GJ 504 using Subaru/HiCIAO within the Strategic Exploration of Exoplanets and Disks with Subaru survey. The planet is substantially colder (
• Janson, M., Brandt, T. D., Moro-Mart{\'\in}, A., Usuda, T., Thalmann, C., Carson, J. C., Goto, M., Currie, T., McElwain, M., Itoh, Y., Fukagawa, M., Crepp, J., Kuzuhara, M., Hashimoto, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Egner, S., , Feldt, M., et al. (2013). The SEEDS Direct Imaging Survey for Planets and Scattered Dust Emission in Debris Disk Systems. \apj, 773(1), 73.
• Janson, M., Brandt, T. D., Moro-Martín, A., Usuda, T., Thalmann, C., Carson, J. C., Goto, M., Currie, T., McElwain, M. W., Itoh, Y., Fukagawa, M., Crepp, J., Kuzuhara, M., Hashimoto, J., Kudo, T., Kusakabe, N., Abe, L., Brandner, W., Egner, S., , Feldt, M., et al. (2013). The seeds direct imaging survey for planets and scattered dust emission in debris disk systems. Astrophysical Journal, 773(1).
  More info

  Abstract: Debris disks around young main-sequence stars often have gaps and cavities which for a long time have been interpreted as possibly being caused by planets. In recent years, several giant planet discoveries have been made in systems hosting disks of precisely this nature, further implying that interactions with planets could be a common cause of such disk structures. As part of the SEEDS high-contrast imaging survey, we are surveying a population of debris-disk-hosting stars with gaps and cavities implied by their spectral energy distributions, in order to attempt to spatially resolve the disk as well as to detect any planets that may be responsible for the disk structure. Here, we report on intermediate results from this survey. Five debris disks have been spatially resolved, and a number of faint point sources have been discovered, most of which have been tested for common proper motion, which in each case has excluded physical companionship with the target stars. From the detection limits of the 50 targets that have been observed, we find that β Pic b-like planets (∼10 M jup planets around G-A-type stars) near the gap edges are less frequent than 15%-30%, implying that if giant planets are the dominant cause of these wide (27 AU on average) gaps, they are generally less massive than β Pic b. © 2013. The American Astronomical Society. All rights reserved.
• Kern, B., Guyon, O., Kuhnert, A., Niessner, A., Martinache, F., & Balasubramanian, K. (2013). Laboratory demonstration of Phase Induced Amplitude Apodization (PIAA) coronagraph with better than 10^-9 contrast. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: We present coronagraphic images from the Phase Induced Amplitude Apodization (PIAA) coronagraph on NASA's High Contrast Imaging Testbed (HCIT) at the Jet Propulsion Lab, showing contrasts of 5×10-10 averaged from 2-4 λ/D, in monochromatic light at 808 nm. In parallel with the coronagraph and its deformable mirror and coronagraphic wavefront control, we also demonstrate a low-order wavefront control system, giving 100× rms suppression of introduced tip/tilt disturbances down to residual levels of 10-3 λ/D. Current limitations, as well as broadband (10% fractional bandpass) preliminary results are discussed. © 2013 SPIE.
• Kuzuhara, M., Tamura, M., Kudo, T., Janson, M., Kandori, R., Brandt, T. D., Thalmann, C., Spiegel, D., Biller, B., Carson, J., Hori, Y., Suzuki, R., Burrows, A., Henning, T., Turner, E. L., McElwain, M. W., Moro-Martín, A., Suenaga, T., Takahashi, Y. H., , Kwon, J., et al. (2013). Direct imaging of a cold jovian exoplanet in orbit around the sun-like star GJ 504. Astrophysical Journal, 774(1).
  More info

  Abstract: Several exoplanets have recently been imaged at wide separations of >10 AU from their parent stars. These span a limited range of ages ( 0.5 mag), implying thick cloud covers. Furthermore, substantial model uncertainties exist at these young ages due to the unknown initial conditions at formation, which can lead to an order of magnitude of uncertainty in the modeled planet mass. Here, we report the direct-imaging discovery of a Jovian exoplanet around the Sun-like star GJ 504, detected as part of the SEEDS survey. The system is older than all other known directly imaged planets; as a result, its estimated mass remains in the planetary regime independent of uncertainties related to choices of initial conditions in the exoplanet modeling. Using the most common exoplanet cooling model, and given the system age of 160 Myr, GJ 504b has an estimated mass of 4 Jupiter masses, among the lowest of directly imaged planets. Its projected separation of 43.5 AU exceeds the typical outer boundary of ∼30 AU predicted for the core accretion mechanism. GJ 504b is also significantly cooler (510 K) and has a bluer color (J-H = -0.23 mag) than previously imaged exoplanets, suggesting a largely cloud-free atmosphere accessible to spectroscopic characterization. Thus, it has the potential of providing novel insights into the origins of giant planets as well as their atmospheric properties. © 2013. The American Astronomical Society. All rights reserved..
• Kuzuhara, M., Tamura, M., Kudo, T., Janson, M., Kandori, R., Brandt, T., Thalmann, C., Spiegel, D., Biller, B., Carson, J., Hori, Y., Suzuki, R., Burrows, A., Henning, T., Turner, E., McElwain, M., Moro-Mart{\'\in}, A., Suenaga, T., Takahashi, Y., , Kwon, J., et al. (2013). Direct Imaging of a Cold Jovian Exoplanet in Orbit around the Sun-like Star GJ 504. \apj, 774(1), 11.
• Lawson, P. R., Belikov, R., Cash, W., Clampin, M., Glassman, T., Guyon, O., Kasdin, N. J., Kern, B. D., Lyon, R., Mawet, D., Moody, D., Samuele, R., Serabyn, E., Sirbu, D., & Trauger, J. (2013). Survey of experimental results in high-contrast imaging for future exoplanet missions. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: We present and compare experimental results in high contrast imaging representing the state of the art in coronagraph and starshade technology. These experiments have been undertaken with the goal of demonstrating the capability of detecting Earth-like planets around nearby Sun-like stars. The contrast of an Earth seen in reflected light around a Sun-like star would be about 1.2 × 10-10. Several of the current candidate technologies now yield raw contrasts of 1.0 × 10-9 or better, and so should enable the detection of Earths, assuming a gain in sensitivity in post-processing of a factor of 10. We present results of coronagraph and starshade experiments conducted at visible and infrared wavelengths. Cross-sections of dark fields are directly compared as a function of field angle and bandwidth. The strength and differences of the techniques are compared. © 2013 SPIE.
• Lozi, J., Belikov, R., Schneider, G., Guyon, O., Pluzhnik, E., Thomas, S. J., & Martinache, F. (2013). Experimental study of a low-order wavefront sensor for the high-contrast coronagraphic imager EXCEDE. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: The mission EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer), selected by NASA for technology development, is designed to study the formation, evolution and architectures of exoplanetary systems and characterize circumstellar environments into stellar habitable zones. It is composed of a 0.7 m telescope equipped with a Phase-Induced Amplitude Apodization Coronagraph (PIAA-C) and a 2000-element MEMS deformable mirror, capable of raw contrasts of 10-6 at 1.2 λ/D and 10-7 above 2 λ/D. One of the key challenges to achieve those contrasts is to remove low-order aberrations, using a Low-Order WaveFront Sensor (LOWFS). An experiment simulating the starlight suppression system is currently developed at NASA Ames Research Center, and includes a LOWFS controlling tip/tilt modes in real time at 500 Hz. The LOWFS allowed us to reduce the tip/tilt disturbances to 10 -3 λ/D rms, enhancing the previous contrast by a decade, to 8 × 10-7 between 1.2 and 2 λ/D. A Linear Quadratic Gaussian (LQG) controller is currently implemented to improve even more that result by reducing residual vibrations. This testbed shows that a good knowledge of the low-order disturbances is a key asset for high contrast imaging, whether for real-time control or for post processing. © 2013 SPIE.
• Newman, K., Belikov, R., Guyon, O., Balasubramanian, K., & Wilson, D. (2013). Achromatic focal plane mask for exoplanet imaging coronagraphy. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: Recent advances in coronagraph technologies for exoplanet imaging have achieved contrasts close to 1e-10 at 4 λ/D and 1e-9 at 2 λ/D in monochromatic light. A remaining technological challenge is to achieve high contrast in broadband light; a challenge that is largely limited by chromaticity of the focal plane mask. The size of a star image scales linearly with wavelength. Focal plane masks are typically the same size at all wavelengths, and must be sized for the longest wavelength in the observational band to avoid starlight leakage. However, this oversized mask blocks useful discovery space from the shorter wavelengths. We present here the design, development, and testing of an achromatic focal plane mask based on the concept of optical filtering by a diffractive optical element (DOE). The mask consists of an array of DOE cells, the combination of which functions as a wavelength filter with any desired amplitude and phase transmission. The effective size of the mask scales nearly linearly with wavelength, and allows significant improvement in the inner working angle of the coronagraph at shorter wavelengths. The design is applicable to almost any coronagraph configuration, and enables operation in a wider band of wavelengths than would otherwise be possible. We include initial results from a laboratory demonstration of the mask with the Phase Induced Amplitude Apodization (PIAA) coronagraph. © 2013 SPIE.
• Peters-Limbach, M. A., Groff, T. D., Kasdin, N. J., Driscoll, D., Galvin, M., Foster, A., Carr, M. A., LeClerc, D., Fagan, R., McElwain, M. W., Knapp, G., Brandt, T., Janson, M., Guyon, O., Jovanovic, N., Martinache, F., Hayashi, M., & Takato, N. (2013). The optical design of CHARIS: An exoplanet IFS for the Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: High-contrast imaging techniques now make possible both imaging and spectroscopy of planets around nearby stars. We present the optical design for the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), a lenslet-based, cryogenic integral field spectrograph (IFS) for imaging exoplanets on the Subaru telescope. The IFS will provide spectral information for 138×138 spatial elements over a 2.07 arcsec × 2.07 arcsec field of view (FOV). CHARIS will operate in the near infrared (λ = 1.15 - 2.5μm) and will feature two spectral resolution modes of R ≈ 18 (low-res mode) and R ≈ 73 (high-res mode). Taking advantage of the Subaru telescope adaptive optics systems and coronagraphs (AO188 and SCExAO), CHARIS will provide sufficient contrast to obtain spectra of young self-luminous Jupiter-mass exoplanets. CHARIS will undergo CDR in October 2013 and is projected to have first light by the end of 2015. We report here on the current optical design of CHARIS and its unique innovations. © 2013 SPIE.
• Spergel, D., Gehrels, N., Breckinridge, J., Donahue, M., Dressler, A., Gaudi, B., Greene, T., Guyon, O., Hirata, C., Kalirai, J., Kasdin, N., Moos, W., Perlmutter, S., Postman, M., Rauscher, B., Rhodes, J., Wang, Y., Weinberg, D., Centrella, J., , Traub, W., et al. (2013). WFIRST-2.4: What Every Astronomer Should Know. arXiv e-prints, arXiv:1305.5425.
• Spergel, D., Gehrels, N., Breckinridge, J., Donahue, M., Dressler, A., Gaudi, B., Greene, T., Guyon, O., Hirata, C., Kalirai, J., Kasdin, N., Moos, W., Perlmutter, S., Postman, M., Rauscher, B., Rhodes, J., Wang, Y., Weinberg, D., Centrella, J., , Traub, W., et al. (2013). Wide-Field InfraRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA Final Report. arXiv e-prints, arXiv:1305.5422.
• Takahashi, Y. H., Narita, N., Hirano, T., Kuzuhara, M., Tamura, M., Kudo, T., Kusakabe, N., Hashimoto, J., Sato, B., Abe, L., Brandner, W., Brandt, T. D., Carson, J. C., Currie, T., Egner, S., Feldt, M., Goto, M., Grady, C. A., Guyon, O., , Hayano, Y., et al. (2013). A Discovery of a Candidate Companion to a Transiting System KOI-94: A Direct Imaging Study for a Possibility of a False Positive. arXiv e-prints, arXiv:1309.2559.
• Takami, M., Karr, J. L., Hashimoto, J., Kim, H., Wisniewski, J., Henning, T., Grady, C. A., Kandori, R., Hodapp, K. W., Kudo, T., Kusakabe, N., Chou, M., Itoh, Y., Momose, M., Mayama, S., Currie, T., Follette, K. B., Kwon, J., Abe, L., , Brandner, W., et al. (2013). High-contrast Near-infrared Imaging Polarimetry of the Protoplanetary Disk around RY TAU. \apj, 772(2), 145.
• Takami, M., Karr, J. L., Hashimoto, J., Kim, H., Wisniewski, J., Henning, T., Grady, C. A., Kandori, R., Hodapp, K. W., Kudo, T., Kusakabe, N., Chou, M., Itoh, Y., Momose, M., Mayama, S., Currie, T., Follette, K. B., Kwon, J., Abe, L., , Brandner, W., et al. (2013). High-contrast near-infrared imaging polarimetry of the protoplanetary disk around RY Tau. Astrophysical Journal, 772(2).
  More info

  Abstract: We present near-infrared coronagraphic imaging polarimetry of RY Tau. The scattered light in the circumstellar environment was imaged at the H band at a high resolution (∼0.″05) for the first time, using Subaru/HiCIAO. The observed polarized intensity (PI) distribution shows a butterfly-like distribution of bright emission with an angular scale similar to the disk observed at millimeter wavelengths. This distribution is offset toward the blueshifted jet, indicating the presence of a geometrically thick disk or a remnant envelope, and therefore the earliest stage of the Class II evolutionary phase. We perform comparisons between the observed PI distribution and disk models with (1) full radiative transfer code, using the spectral energy distribution (SED) to constrain the disk parameters; and (2) monochromatic simulations of scattered light which explore a wide range of parameters space to constrain the disk and dust parameters. We show that these models cannot consistently explain the observed PI distribution, SED, and the viewing angle inferred by millimeter interferometry. We suggest that the scattered light in the near-infrared is associated with an optically thin and geometrically thick layer above the disk surface, with the surface responsible for the infrared SED. Half of the scattered light and thermal radiation in this layer illuminates the disk surface, and this process may significantly affect the thermal structure of the disk. © 2013. The American Astronomical Society. All rights reserved.
• Thalmann, C., Janson, M., Buenzli, E., Brandt, T. D., Wisniewski, J. P., Dominik, C., Carson, J., McElwain, M. W., Currie, T., Knapp, G. R., Moro-Martín, A., Usuda, T., Abe, L., Brandner, W., Egner, S., Feldt, M., Golota, T., Goto, M., Guyon, O., , Hashimoto, J., et al. (2013). Imaging discovery of the debris disk around HIP 79977. Astrophysical Journal Letters, 763(2).
  More info

  Abstract: We present Subaru/HiCIAO H-band high-contrast images of the debris disk around HIP 79977, whose presence was recently inferred from an infrared excess. Our images resolve the disk for the first time, allowing characterization of its shape, size, and dust grain properties. We use angular differential imaging (ADI) to reveal the disk geometry in unpolarized light out to a radius of 2″, as well as polarized differential imaging to measure the degree of scattering polarization out to 1.″5. In order to strike a favorable balance between suppression of the stellar halo and conservation of disk flux, we explore the application of principal component analysis to both ADI and reference star subtraction. This allows accurate forward modeling of the effects of data reduction on simulated disk images, and thus direct comparison with the imaged disk. The resulting best-fit values and well-fitting intervals for the model parameters are a surface brightness power-law slope of Sout = -3.2[-3.6, -2.9], an inclination of i = 84°[81°, 86°], a high Henyey-Greenstein forward-scattering parameter of g = 0.45[0.35, 0.60], and a non-significant disk-star offset of u = 3.0[-1.5, 7.5] AU = 24[-13, 61] mas along the line of nodes. Furthermore, the tangential linear polarization along the disk rises from 10% at 0.″5 to 45% at 1.″5. These measurements paint a consistent picture of a disk of dust grains produced by collisional cascades and blown out to larger radii by stellar radiation pressure. © 2013. The American Astronomical Society. All rights reserved.
• Thalmann, C., Janson, M., Buenzli, E., Brandt, T., Wisniewski, J., Dominik, C., Carson, J., McElwain, M., Currie, T., Knapp, G., Moro-Mart{\'\in}, A., Usuda, T., Abe, L., Brandner, W., Egner, S., Feldt, M., Golota, T., Goto, M., Guyon, O., , Hashimoto, J., et al. (2013). Imaging Discovery of the Debris Disk around HIP 79977. \apjl, 763(2), L29.
• Thomas, S., Pluzhnik, E., Lozi, J., Belikov, R., Witteborn, F., Greene, T., Schneider, G., & Guyon, O. (2013). Improving image contrast for the direct detection of exo-planets at small inner working angles. Proceedings of SPIE - The International Society for Optical Engineering, 8864.
  More info

  Abstract: The detection of extrasolar planets, using both space- and ground-based telescopes, is one of the most exciting fields in astronomy today, with the ultimate goal of the direct direction of earth-like planets in the habitable zone. It is with this vision that the explorer mission EXCEDE selected by NASA for technology development, is designed. EXCEDE (Exoplanetary Circumstellar Environment and Disk Explorer) is composed of a 0.7 m telescope equipped with a Phase-Induced Amplitude Apodization Coronagraph (PIAA-C) and a 2000-element MEMS deformable mirror, capable of raw contrasts of 10-6 at 1.2 λ/D and 10-7 above 2 λ/D. Obtaining these contrasts requires precise wavefront control algorithms used in conjuncture with deformable mirrors. Unlike other optical systems, where the goal is to obtain the best wavefront, we aim at canceling the diffracted light coming from the parent star in a specific region to increase signal-to-noise of the planet. To do so, we use wavefront control techniques, such as Electric Field Conjugation (EFC) and speckle nulling, already developed and soon to be operational on 8-m class telescopes. One caveat is that the demonstration was done at moderate separations (r< 3λ/D). In this paper, we present tricks and techniques to perform high-contrast imaging at 1.2 λ/d using the NASA Ames Coronagraph Experiment testbed. © 2013 SPIE.
• Yamamoto, K., Matsuo, T., Shibai, H., Itoh, Y., Konishi, M., Sudo, J., Tanii, R., Fukagawa, M., Sumi, T., Kudo, T., Hashimoto, J., Kusakabe, N., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Currie, T., Egner, S. E., Feldt, M., , Goto, M., et al. (2013). Direct Imaging Search for Extrasolar Planets in the Pleiades. \pasj, 65, 90.
• Yamamoto, K., Matsuo, T., Shibai, H., Itoh, Y., Konishi, M., Sudo, J., Tanii, R., Fukagawa, M., Sumi, T., Kudo, T., Hashimoto, J., Kusakabe, N., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Currie, T., Egner, S. E., Feldt, M., , Goto, M., et al. (2013). Direct imaging search for extrasolar planets in the pleiades. Publications of the Astronomical Society of Japan, 65(4).
  More info

  Abstract: We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the H and KS bands using HiCIAO combined with adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the H band around 9 stars. Five of these 13 were confirmed to be background stars by measurement of their proper motion. One was not found in the second epoch observation, and thus was not a background or companion object. One had multi-epoch images, but the precision of its proper motion was not sufficient to conclude whether it was a background object. Four other candidates are waiting for second-epoch observations to determine their proper motion. Finally, the remaining two were confirmed to be 60MJ brown dwarf companions orbiting around HD 23514 (G0) and HII 1348 (K5), respectively, as had been reported in previous studies. In our observations, the average detection limit for a point source was 20.3 mag in the H band beyond 1:005 from the central star. On the basis of this detection limit, we calculated the detection efficiency to be 90% for a planet with 6 to 12 Jovian masses and a semi-major axis of 50-1000 AU. For this reason we extrapolated the distribution of the planet mass and the semi-major axis derived from radial velocity observations, and adopted the planet evolution model Baraffe et al. (2003, A&A, 402, 701). Since there was no detection of a planet, we estimated the frequency of such planets to be less than 17.9% (2) around one star of the Pleiades cluster. © 2013. Astronomical Society of Japan.
• Ammons, S. M., Bendek, E. A., Guyon, O., Macintosh, B., & Savransky, D. (2012). Theoretical limits on bright star astrometry with multi-conjugate adaptive optics using a diffractive pupil. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: We present a ground-based technique to detect or follow-up long-period exoplanets via precise relative astrometry of host stars using Multi-Conjugate Adaptive Optics (MCAO) on 8 meter telescopes equipped with diffractive masks. MCAO improves relative astrometry by sharpening PSFs, reducing the star centroiding error, and by providing a spatially stable, more easily modeled PSF. However, exoplanet mass determination requires multi-year reference grid stability of ∼10-100 uas or nanometer-level stability on the long-term average of out-of-pupil phase errors, which is difficult to achieve with MCAO. The diffractive pupil technique calibrates dynamic distortion via extended diffraction spikes generated by a dotted primary mirror, which are referenced against a grid of background stars. We calculate the astrometic performance of a diffractive 8-meter telescope with diffraction-limited MCAO in K using analytical techniques and a simplified MCAO simulation. Referencing the stellar grid to the diffraction spikes negates the cancellation of Differential Tip/Tilt Jitter normally achieved with MCAO. However, due to the substantial gains associated with sharper, more stable PSFs, diffractive 8-m MCAO reaches ∼ 4-6 μas relative astrometric error per coordinate in one hour on a bright target star (K - 7) in fields of moderate stellar density (∼10 stars arcmin-2). Final relative astrometric precision with MCAO is limited by atmospheric differential tip/tilt jitter. © 2012 SPIE.
• Belikov, R., Pluzhnik, E., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., Schneider, G., Guyon, O., & Tenerelli, D. (2012). EXCEDE technology development I: First demonstrations of high contrast at 1.2 λ/D for an explorer space telescope mission. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: Coronagraph technology is advancing and promises to enable space telescopes capable of seeing debris disks as well as seeing and spectrally characterizing exo-Earths. Recently, NASA's explorer program has selected the EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer) mission concept for technology development. EXCEDE is a 0.7m space telescope concept designed to achieve raw contrasts of 1e-6 at an inner working angle of 1.2 λ/D and 1e- 7 at 2 λ/D. In addition to doing fundamental science on debris disks, EXCEDE will also serve as a technological and scientific precursor for an exo-Earth imaging mission. EXCEDE uses a Starlight Suppression System (SSS) based on the Phase Induced Amplitude Apodization (PIAA) coronagraph to provide high throughput and high contrast close to the diffraction limit, enabling aggressive performance on small telescopes. We report on the latest progress in developing the SSS and present coronagraphic performance results from our air testbed at NASA Ames. Our results include a lab demonstration of 1e-5 contrast at 1.2 λ/D, 1.3e-6 contrast at 1.4 λ/D and 2e-8 at 2 λ/D in monochromatic light. In addition, we discuss tip-tilt instabilities, which are believed to be our main limiting factor at present, and ways of characterizing them. © 2012 SPIE.
• Bendek, E. A., Ammons, S. M., Belikov, R., Pluzhnik, E., & Guyon, O. (2012). High-precision astrometry laboratory demonstration for exoplanet detection using a diffractive pupil telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: Detection of earth-size exoplanets using the astrometric signal of the host star requires sub microarcsecond measurement precision. One major challenge in achieving this precision using a medium-size (
• Blain, C., Guyon, O., Martinache, F., Bradley, C., & Clergeon, C. (2012). Open-loop control of SCExAO's MEMS deformable mirror using the Fast Iterative Algorithm: Speckle control performances. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: Micro-Electro-Mechanical Systems (MEMS) deformable mirrors (DMs) are widely utilized in astronomical Adaptive Optics (AO) instrumentation. High precision open-loop control of MEMS DMs has been achieved by developing a high accuracy DM model, the Fast Iterative Algorithm (FIA), a physics-based model allowing precise control of the DM shape. Accurate open-loop control is particularly critical for the wavefront control of High-Contrast Imaging (HCI) instruments to create a dark hole area free of most slow and quasi-static speckles which remain the limiting factor for direct detection and imaging of exoplanets. The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system is one of these high contrast imaging instruments and uses a 1024-actuator MEMS deformable mirror (DM) both in closed-loop and open-loop. The DM is used to modulate speckles in order to distinguish (i) speckles due to static and slow-varying residual aberrations from (ii) speckles due to genuine structures, such as exoplanets. The FIA has been fully integrated into the SCExAO wavefront control software and we report the FIA's performance for the control of speckles in the focal plane. © 2012 SPIE.
• Boccaletti, A., Schneider, J., Traub, W., Lagage, P., Stam, D., Gratton, R., Trauger, J., Cahoy, K., Snik, F., Baudoz, P., Galicher, R., Reess, J., Mawet, D., Augereau, J., Patience, J., Kuchner, M., Wyatt, M., Pantin, E., Maire, A., , Vérinaud, C., et al. (2012). SPICES: Spectro-polarimetric imaging and characterization of exoplanetary systems: From planetary disks to nearby Super Earths. Experimental Astronomy, 34(2), 355-384.
  More info

  Abstract: SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450-900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/2022, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1. 5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0. 5-10 AU) from nearby stars (
• Carlotti, A., Kasdin, N. J., Martinache, F., Vanderbei, R. J., Young, E. J., Che, G., Groff, T. D., & Guyon, O. (2012). Fully optimized shaped pupils: Preparation for a test at the Subaru telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8446.
  More info

  Abstract: The SCExAO instrument at the Subaru telescope, mainly based on a PIAA coronagraph can benefit from the addition of a robust and simple shaped pupil coronagraph. New shaped pupils, fully optimized in 2 dimensions, make it possible to design optimal apodizers for arbitrarily complex apertures, for instance on-axis telescopes such as the Subaru telescope. We have designed several masks with inner working angles as small as 2.5 λ/D, and for high-contrast regions with different shapes. Using Princeton University nanofabrication facilities, we have manufactured two masks by photolithography. These masks have been tested in the laboratory, both in Princeton and in the facilities of the National Astronomical Observatory of Japan (NAOJ) in Hilo. The goal of this work is to prepare tests on the sky of a shaped pupil coronagraph in 2012. © 2012 SPIE.
• Dong, R., Hashimoto, J., Rafikov, R., Zhu, Z., Whitney, B., Kudo, T., Muto, T., Brandt, T., McClure, M. K., Wisniewski, J., Abe, L., Brandner, W., Carson, J., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2012). The Structure of Pre-transitional Protoplanetary Disks. I. Radiative Transfer Modeling of the Disk+Cavity in the PDS 70 System. \apj, 760(2), 111.
• Dong, R., Hashimoto, J., Rafikov, R., Zhu, Z., Whitney, B., Kudo, T., Muto, T., Brandt, T., McClure, M. K., Wisniewski, J., Abe, L., Brandner, W., Carson, J., Egner, S., Feldt, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2012). The structure of pre-transitional protoplanetary disks. I. Radiative transfer modeling of the disk+cavity in the PDS 70 system. Astrophysical Journal, 760(2).
  More info

  Abstract: Through detailed radiative transfer modeling, we present a disk+cavity model to simultaneously explain both the spectral energy distribution (SED) and Subaru H-band polarized light imaging for the pre-transitional protoplanetary disk PDS 70. In particular, we are able to match not only the radial dependence but also the absolute scale of the surface brightness of the scattered light. Our disk model has a cavity 65 AU in radius, which is heavily depleted of sub-micron-sized dust grains, and a small residual inner disk that produces a weak but still optically thick near-IR excess in the SED. To explain the contrast of the cavity's edge in the Subaru image, a factor of 1000 depletion for the sub-micron-sized dust inside the cavity is required. The total dust mass of the disk may be on the order of 10 -4M, only weakly constrained due to the lack of long-wavelength observations and the uncertainties in the dust model. The scale height of the sub-micron-sized dust is 6 AU at the cavity edge, and the cavity wall is optically thick in the vertical direction at H-band. PDS 70 is not a member of the class of (pre-)transitional disks identified by Dong et al., whose members only show evidence of the cavity in the millimeter-size dust but not the sub-micron-sized dust in resolved images. The two classes of (pre-)transitional disks may form through different mechanisms, or they may simply be at different evolution stages in the disk-clearing process. © 2012. The American Astronomical Society. All rights reserved..
• Dong, R., Rafikov, R., Zhu, Z., Hartmann, L., Whitney, B., Brandt, T., Muto, T., Hashimoto, J., Grady, C., Follette, K., Kuzuhara, M., Tanii, R., Itoh, Y., Thalmann, C., Wisniewski, J., Mayama, S., Janson, M., Abe, L., Brandner, W., , Carson, J., et al. (2012). The Missing Cavities in the SEEDS Polarized Scattered Light Images of Transitional Protoplanetary Disks: A Generic Disk Model. \apj, 750(2), 161.
• Dong, R., Rafikov, R., Zhu, Z., Hartmann, L., Whitney, B., Brandt, T., Muto, T., Hashimoto, J., Grady, C., Follette, K., Kuzuhara, M., Tanii, R., Itoh, Y., Thalmann, C., Wisniewski, J., Mayama, S., Janson, M., Abe, L., Brandner, W., , Carson, J., et al. (2012). The missing cavities in the seeds polarized scattered light images of transitional protoplanetary disks: A generic disk model. Astrophysical Journal, 750(2).
  More info

  Abstract: Transitional circumstellar disks around young stellar objects have a distinctive infrared deficit around 10 μm in their spectral energy distributions, recently measured by the Spitzer Infrared Spectrograph (IRS), suggesting dust depletion in the inner regions. These disks have been confirmed to have giant central cavities by imaging of the submillimeter continuum emission using the Submillimeter Array (SMA). However, the polarized near-infrared scattered light images for most objects in a systematic IRS/SMA cross sample, obtained by HiCIAO on the Subaru telescope, show no evidence for the cavity, in clear contrast with SMA and Spitzer observations. Radiative transfer modeling indicates that many of these scattered light images are consistent with a smooth spatial distribution for μm-sized grains, with little discontinuity in the surface density of the μm-sized grains at the cavity edge. Here we present a generic disk model that can simultaneously account for the general features in IRS, SMA, and Subaru observations. Particularly, the scattered light images for this model are computed, which agree with the general trend seen in Subaru data. Decoupling between the spatial distributions of the μm-sized dust and mm-sized dust inside the cavity is suggested by the model, which, if confirmed, necessitates a mechanism, such as dust filtration, for differentiating the small and big dust in the cavity clearing process. Our model also suggests an inwardly increasing gas-to-dust ratio in the inner disk, and different spatial distributions for the small dust inside and outside the cavity, echoing the predictions in grain coagulation and growth models. © © 2012. The American Astronomical Society. All rights reserved..
• Dressler, A., Spergel, D., Mountain, M., Postman, M., Elliott, E., Bendek, E., Bennett, D., Dalcanton, J., Gaudi, S., Gehrels, N., Guyon, O., Hirata, C., Kalirai, J., Kasdin, N. J., Kruk, J., Macintosh, B., Malhotra, S., Penny, M., Perlmutter, S., , Rieke, G., et al. (2012). Exploring the NRO Opportunity for a Hubble-sized Wide-field Near-IR Space Telescope -- NEW WFIRST. arXiv e-prints, arXiv:1210.7809.
• Garrel, V., Guyon, O., & Baudoz, P. (2012). A Highly Efficient Lucky Imaging Algorithm: Image Synthesis Based on Fourier Amplitude Selection. \pasp, 124(918), 861.
• Garrel, V., Guyon, O., & Baudoz, P. (2012). A highly efficient lucky imaging algorithm: Image synthesis based on fourier amplitude selection. Publications of the Astronomical Society of the Pacific, 124(918), 861-867.
  More info

  Abstract: We propose a new algorithm dramatically enhancing the efficiency of the lucky imaging technique for AO-corrected images in the visible range. It is achieved by a selection based on the relative strength of signal for each spatial frequency in the Fourier domain, making a more efficient use of information contained in each frame. Realistic simulations show that our algorithm allows us to reach the diffraction limit in the visible range on an AO-equipped 8 m telescope and enhances the Strehl ratio of an AO long exposure by a factor of up to 4. It outperforms the lucky imaging technique at an equivalent selection ratio. The fraction of selected data in simulation is also boosted from two to eight times for a given Strehl-ratio performance. © 2012. The Astronomical Society of the Pacific. All rights reserved.
• Guyon, O. (2012). Optical tricks to image habitable planets around nearby stars. Frontiers in Optics, FIO 2012.
  More info

  Abstract: Direct imaging of exoplanets is essential to characterize their surfaces and atmospheres, and identify biological activity. Direct observation of exoplanets is however extremely challenging, due to the large ratio between starlight and planet light, combined with the small angular separation between the two objects. Conventional telescopes cannot perform such observations, and newly developed optical techniques, specifically designed for high contrast imaging, must be employed. High contrast imaging systems include two essential subsystems: (1) a coronagraph must optically block bright starlight while preserving the faint light from the planet(s) nearby and (2) an adaptive optics system must maintain the exquisite wavefront quality necessary for the coronagraph to operate at high contrast. © OSA 2012.
• Guyon, O., & Martinache, F. (2012). Achieving high precision photometry for transiting exoplanets with a low cost robotic DSLR-based imaging system. Proceedings of SPIE - The International Society for Optical Engineering, 8444.
  More info

  Abstract: We describe a low cost high precision photometric imaging system, which has been in robotic operation for one and half year on the Mauna Loa observatory (Hawaii). The system, which can be easily duplicated, is composed of commercially available components, offers a 150 sq deg field with two 70mm entrance apertures, and 6-band simultaneous photometry at a 0.01 Hz sampling. The detectors are low-cost commercial 3-color CMOS array, which we show is an attractive cost-effective choice for high precision transit photometry. We describe the design of the system and show early results. A new data processing technique was developed to overcome pixelization and color errors. We show that this technique, which can also be applied on non-color imaging systems, essentially removes pixelization errors in the photometric signal, and we demonstrate on-sky photometric precision approaching fundamental error sources (photon noise and atmospheric scintillation). We conclude that our approach is ideally suited for exoplanet transit survey with multiple units. We show that in this scenario, the success metric is purely cost per etendue, which is at less than $10000s per square meter square degree for our system. © 2012 SPIE.
• Guyon, O., Bendek, E. A., Eisner, J. A., Angel, R., Woolf, N. J., Milster, T. D., Ammons, S. M., Shao, M., Shaklan, S., Levine, M., Nemati, B., Pitman, J., Woodruff, R. A., & Belikov, R. (2012). High-precision Astrometry with a Diffractive Pupil Telescope. \apjs, 200(2), 11.
• Guyon, O., Bendek, E., Ammons, S. M., Shao, M., Shaklan, S., Woodruff, R. A., Belikov, R., & Milster, T. (2012). Characterization of habitable exoplanets with simultaneous coronagraphy and astrometry with a single aperture telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: With sub-microarcsecond astrometry, exoplanets can be identified and their masses measured. Coronagraphic imaging of these exoplanets is required to study their atmospheres and surfaces in sufficient detail to identify possible signs of biological activity. We show how both measurements can be simultaneously acquired with a single telescope in which the central field is directed to a coronagraph instrument providing high contrast images, while the surrounding field is imaged with a wide field camera in which numerous faint background stars are used as an astrometric reference. To calibrate astrometric distortions due to optics and focal plane detector array imperfections and variations, we propose to place small dark spots on the telescope primary mirror. The spots, arranged in a regular grid containing no low spatial frequencies, do not affect the coronagraph performance. In the wide field image, they create diffraction spikes originating from the central bright star, which are affected by changes in intrumental distortions in exactly the same way as the background stars used for reference, thus allowing calibration of instrumental errors to micro-arcsecond level. We show that combining simultaneous astrometric and coronagraphic measurements allows reliable detection and characterization of exoplanets. Recent laboratory tests performed at the University of Arizona and NASA Ames validate the concept, demonstrating both the ability to accurately calibrate astrometric distortions, and compatibility with high contrast imaging systems. © 2012 SPIE.
• Guyon, O., Martinache, F., Cady, E., Belikov, R., Kunjithapatham, B., Wilson, D., Clergeon, C., & Mateen, M. (2012). How ELTs will acquire the first spectra of rocky habitable planets. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: ELTs will offer angular resolution around 10mas in the near-IR and unprecedented sensitivity. While direct imaging of Earth-like exoplanets around Sun-like stars will stay out of reach of ELTs, we show that habitable planets around nearby M-type main sequence stars can be directly imaged. For about 300 nearby M dwarfs, the angular separation at maximum elongation is at or beyond 1 λ/D in the near-IR for an ELT. The planet to star contrast is 1e-7 to 1e-8, similar to what the upcoming generation of Extreme-AO systems will achieve on 8-m telescopes, and the potential planets are sufficiently bright for near-IR spectroscopy. We show that the technological solutions required to achieve this goal exist. For example, the PIAACMC coronagraph can deliver full starlight rejection, 100% throughput and sub-λ/D IWA for the EELT, GMT and TMT pupils. A closely related coronagraph is part of SCExAO on Subaru. We conclude that large ground-based telescopes will acquire the first high quality spectra of habitable planets orbiting M-type stars, while future space mission(s) will later target F-G-K type stars. © 2012 SPIE.
• Guyon, O., Schneider, G., Belikov, R., & Tenerelli, D. J. (2012). The EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE). Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: We present an overview of the EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE), selected by NASA for technology development and maturation. EXCEDE will study the formation, evolution and architectures of exoplanetary systems, and characterize circumstellar environments into stellar habitable zones. EXCEDE provides contrast-limited scattered-light detection sensitivities ̃ 1000x greater than HST or JWST coronagraphs at a much smaller effective inner working angle (IWA), thus enabling the exploration and characterization of exoplanetary circumstellar disks in currently inaccessible domains. EXCEDE will utilize a laboratory demonstrated high-performance Phase Induced Amplitude Apodized Coronagraph (PIAA-C) integrated with a 70 cm diameter unobscured aperture visible light telescope. The EXCEDE PIAA-C will deliver star-to-disk augmented image contrasts of < 10E-8 and a 1.2 λ/D IWA or 0.14" with a wavefront control system utilizing a 2000-element MEMS DM and fast steering mirror. EXCEDE will provide 0.12" spatial resolution at 0.4 μm with dust detection sensitivity to levels of a few tens of zodis with two-band imaging polarimetry. EXCEDE is a science-driven technology pathfinder that will advance our understanding of the formation and evolution of exoplanetary systems, placing our solar system in broader astrophysical context, and will demonstrate the high contrast technologies required for larger-scale follow-on and multi-wavelength investigations on the road to finding and characterizing exo-Earths in the years ahead. © 2012 SPIE.
• Hashimoto, J., Dong, R., Kudo, T., Honda, M., McClure, M. K., Zhu, Z., Muto, T., Wisniewski, J., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C. A., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2012). Polarimetric imaging of large cavity structures in the pre-transitional protoplanetary disk around PDS 70: Observations of the disk. Astrophysical Journal Letters, 758(1).
  More info

  Abstract: We present high-resolution H-band polarized intensity (FWHM = 0″.1: 14AU) and L′-band imaging data (FWHM = 0″.11: 15AU) of the circumstellar disk around the weak-lined T Tauri star PDS 70 in Centaurus at a radial distance of 28AU (0″.2) up to 210AU (1″.5). In both images, a giant inner gap is clearly resolved for the first time, and the radius of the gap is ∼70AU. Our data show that the geometric center of the disk shifts by ∼6AU toward the minor axis. We confirm that the brown dwarf companion candidate to the north of PDS 70 is a background star based on its proper motion. As a result of spectral energy distribution fitting by Monte Carlo radiative transfer modeling, we infer the existence of an optically thick inner disk at a fewAU. Combining our observations and modeling, we classify the disk of PDS 70 as a pre-transitional disk. Furthermore, based on the analysis of L′-band imaging data, we put an upper limit of ∼30 to ∼50 M J on the mass of companions within the gap. Taking into account the presence of the large and sharp gap, we suggest that the gap could be formed by dynamical interactions of sub-stellar companions or multiple unseen giant planets in the gap. © 2012. The American Astronomical Society. All rights reserved.
• Hashimoto, J., Dong, R., Kudo, T., Honda, M., McClure, M., Zhu, Z., Muto, T., Wisniewski, J., Abe, L., Brandner, W., Brandt, T., Carson, J., Egner, S., Feldt, M., Fukagawa, M., Goto, M., Grady, C., Guyon, O., Hayano, Y., , Hayashi, M., et al. (2012). Polarimetric Imaging of Large Cavity Structures in the Pre-transitional Protoplanetary Disk around PDS 70: Observations of the Disk. \apjl, 758(1), L19.
• Kawahara, H., Matsuo, T., Takami, M., Fujii, Y., Kotani, T., Murakami, N., Tamura, M., & Guyon, O. (2012). Can Ground-based Telescopes Detect the Oxygen 1.27 \ensuremath{\mu}m Absorption Feature as a Biomarker in Exoplanets?. \apj, 758(1), 13.
• Kawahara, H., Matsuo, T., Takami, M., Fujii, Y., Kotani, T., Murakami, N., Tamura, M., & Guyon, O. (2012). Can ground-based telescopes detect the oxygen 1.27 μm absorption feature as a biomarker in exoplanets?. Astrophysical Journal, 758(1).
  More info

  Abstract: The oxygen absorption line imprinted in the scattered light from Earth-like planets has been considered the most promising metabolic biomarker for exolife. We examine the feasibility of the detection of the 1.27 μm oxygen band from habitable exoplanets, in particular, around late-type stars observed with a future instrument on a 30m class ground-based telescope. We analyzed the night airglow around 1.27 μm with the IRCS/echelle spectrometer on Subaru and found that the strong telluric emission from atmospheric oxygen molecules declines by an order of magnitude by midnight. By compiling nearby star catalogs combined with the sky background model, we estimate the detectability of the oxygen absorption band from an Earth twin, if it exists, around nearby stars. We find that the most dominant source of photon noise for the oxygen 1.27 μm band detection comes from the night airglow if the contribution of the stellar point-spread function (PSF) halo is suppressed enough to detect the planet. We conclude that the future detectors, for which the detection contrast is limited by photon noise, can detect the oxygen 1.27 μm absorption band of Earth twins for 50 candidates of the late-type star. This paper demonstrates the importance of deploying a small inner working angle as an efficient coronagraph and extreme adaptive optics on extremely large telescopes, and clearly shows that doing so will enable the study of potentially habitable planets. © © 2012. The American Astronomical Society. All rights reserved..
• Kotani, T., Enya, K., Nakagawa, T., Matsuhara, H., Kataza, H., Kawada, M., Mita, M., Komatsu, K., Uchida, H., Fujiwara, K., Mitani, S., Sakai, S., Haze, K., Kaneda, H., Oyabu, S., Ishihara, D., Miyata, T., Sako, S., Nakamura, T., , Asano, K., et al. (2012). SPICA coronagraph instrument: Characterization of atmospheres and physical parameters of giant planets by direct imaging and spectroscopy. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: We present the current status of the development of the SPICA Coronagraph Instrument (SCI). SPICA is a nextgeneration 3-meter class infrared telescope, which will be launched in 2022. SCI is high-contrast imaging, spectroscopic instrument mainly for direct detection and spectroscopy of extra-solar planets in the near-to-mid infrared wavelengths to characterize their atmospheres, physical parameters and evolutionary scenarios. SCI is now under the international review process. In this paper, we present a science case of SCI. The main targets of SCI, not only for direct imaging but also for spectroscopy, are young to matured giant planets. We will also show that some of known exoplanets by groundbased direct detection are good targets for SCI, and a number of direct detection planets that are suitable for SCI will be significantly increased in the next decade. Second, a general design of SCI and a key technology including a new highthroughput binary mask coronagraph, will be presented. Furthermore, we will show that SCI is potentially capable of achieving 10-6 contrast by a PSF subtraction method, even with a telescope pointing error. This contrast enhancement will be important to characterize low-mass and cool planets. © 2012 SPIE.
• Kulcsár, C., Sivo, G., Raynaud, H., Neichel, B., Rigaut, F., Christou, J., Guesalaga, A., Correia, C., Véran, J., Gendron, É., Vidal, F., Rousset, G., Morris, T., Esposito, S., Quirós-Pacheco, F., Agapito, G., Fedrigo, E., Pettazzi, L., Clare, R., , Muradore, R., et al. (2012). Vibrations in AO control: A short analysis of on-sky data around the world. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: We present in this paper an analysis of several tip-tilt on-sky data registered on adaptive optics systems installed on different telescopes (Gemini South, William Herschel Telescope, Large Binocular Telescope, Very Large Telescope, Subaru). Vibration peaks can be detected, and it is shown that their presence and location may vary, and that their origin is not always easy to determine. Mechanical solution that have been realized to mitigate vibrations are presented. Nevertheless, residual vibrations may still affect the instruments' performance, ranging from narrow high frequency vibration peaks to wide low frequency windshake-type perturbations. Power Spectral Densities (PSDs) of on-sky data are presented to evidence these features. When possible, indications are given regarding the gain in performance that could be achieved with adequate controllers accounting for vibration mitigation. Two examples of controller identification and design illustrate their ability to compensate for various types of disturbances (turbulence, windshake, vibration peaks, ...), showing a significant gain in performance. © 2012 SPIE.
• Kusakabe, N., Grady, C. A., Sitko, M. L., Hashimoto, J., Kudo, T., Fukagawa, M., Muto, T., Wisniewski, J. P., Min, M., Mayama, S., Werren, C., Day, A. N., Beerman, L. C., Lynch, D. K., Russell, R. W., Brafford, S. M., Kuzuhara, M., Brandt, T. D., Abe, L., , Brandner, W., et al. (2012). High-contrast near-infrared polarization imaging of MWC480. Astrophysical Journal, 753(2).
  More info

  Abstract: One of the key predictions of modeling from the IR excess of Herbig Ae stars is that for protoplanetary disks, where significant grain growth and settling has occurred, the dust disk has flattened to the point that it can be partially or largely shadowed by the innermost material at or near the dust sublimation radius. When the self-shadowing has already started, the outer disk is expected to be detected in scattered light only in the exceptional cases when the scale height of the dust disk at the sublimation radius is smaller than usual. High-contrast imaging combined with the IR spectral energy distribution allow us to measure the degree of flattening of the disk, as well as to determine the properties of the outer disk. We present polarimetric differential imaging in the H band obtained with Subaru/HiCIAO of one such system, MWC480. The HiCIAO data were obtained at a historic minimum of the NIR excess. The disk is detected in scattered light from 02 to 10 (27.4-137 AU). Together with the marginal detection of the disk from 1998 February 24 by Hubble Space Telescope/NICMOS, our data constrain the opening half-angle for the disk to lie between 13 ≤θ ≤ 22. When compared with similar measures in CO for the gas disk from the literature, the dust disk subtends only 30% of the gas disk scale height (H/R 0.03). Such a dust disk is a factor of 5-7 flatter than transitional disks, which have structural signatures that giant planets have formed. © 2012. The American Astronomical Society. All rights reserved..
• Kusakabe, N., Grady, C., Sitko, M., Hashimoto, J., Kudo, T., Fukagawa, M., Muto, T., Wisniewski, J., Min, M., Mayama, S., Werren, C., Day, A., Beerman, L., Lynch, D., Russell, R., Brafford, S., Kuzuhara, M., Brandt, T., Abe, L., , Brandner, W., et al. (2012). High-contrast Near-infrared Polarization Imaging of MWC480. \apj, 753(2), 153.
• Lawson, P. R., Poyneer, L., Barrett, H., Frazin, R., Caucci, L., Devaney, N., Furenlid, L., Ladysz, S. G., Guyon, O., Krista, J., Maire, J., Marois, C., Mawet, D., Mouillet, D., Mugnier, L., Pearson, I., Perrin, M., Pueyo, L., & Savransky, D. (2012). On advanced estimation techniques for exoplanet detection and characterization using ground-based coronagraphs. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: The direct imaging of planets around nearby stars is exceedingly difficult. Only about 14 exoplanets have been imaged to date that have masses less than 13 times that of Jupiter. The next generation of planet-finding coronagraphs, including VLT-SPHERE, the Gemini Planet Imager, Palomar P1640, and Subaru HiCIAO have predicted contrast performance of roughly a thousand times less than would be needed to detect Earth-like planets. In this paper we review the state of the art in exoplanet imaging, most notably the method of Locally Optimized Combination of Images (LOCI), and we investigate the potential of improving the detectability of faint exoplanets through the use of advanced statistical methods based on the concepts of the ideal observer and the Hotelling observer. We propose a formal comparison of techniques using a blind data challenge with an evaluation of performance using the Receiver Operating Characteristic (ROC) and Localization ROC (LROC) curves. We place particular emphasis on the understanding and modeling of realistic sources of measurement noise in ground-based AO-corrected coronagraphs. The work reported in this paper is the result of interactions between the co-authors during a week-long workshop on exoplanet imaging that was held in Squaw Valley, California, in March of 2012. © 2012 SPIE.
• Martinache, F., Guyon, O., Clergeon, C., & Blain, C. (2012). Speckle Control with a Remapped-Pupil PIAA Coronagraph. \pasp, 124(922), 1288.
• Martinache, F., Guyon, O., Clergeon, C., & Blain, C. (2012). Speckle control with a remapped-pupil PIAA coronagraph. Publications of the Astronomical Society of the Pacific, 124(922), 1288-1294.
  More info

  Abstract: Phase-induced amplitude apodization (PIAA) is a well-demonstrated high-contrast technique that uses an intermediate remapping of the pupil for high-contrast coronagraphy (apodization), before restoring it to recover classical imaging capabilities. This paper presents the first demonstration of complete speckle control loop with one such PIAA coronagraph. We show the presence of a complete set of remapping optics (the so-called PIAA and matching inverse PIAA) is transparent to the wavefront control algorithm. Simple focal-plane-based wavefront control algorithms can thus be employed, without the need to model remapping effects. Using the Subaru Coronagraphic Extreme AO (SCExAO) instrument built for the Subaru Telescope, we show, using a calibration source, that a complete PIAA coronagraph is compatible with a simple implementation of a speckle nulling technique, and demonstrate the benefit of the PIAA for high-contrast imaging at small angular separation. © 2012. The Astronomical Society of the Pacific.
• Mawet, D., Pueyo, L., Lawson, P., Mugnier, L., Traub, W., Boccaletti, A., Trauger, J., Gladysz, S., Serabyn, E., Milli, J., Belikov, R., Kasper, M., Baudoz, P., MacIntosh, B., Marois, C., Oppenheimer, B., Barrett, H., Beuzit, J., Devaney, N., , Girard, J., et al. (2012). Review of small-angle coronagraphic techniques in the wake of ground-based second-generation adaptive optics systems. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: Small-angle coronagraphy is technically and scientifically appealing because it enables the use of smaller telescopes, allows covering wider wavelength ranges, and potentially increases the yield and completeness of circumstellar environment - exoplanets and disks - detection and characterization campaigns. However, opening up this new parameter space is challenging. Here we will review the four posts of high contrast imaging and their intricate interactions at very small angles (within the first 4 resolution elements from the star). The four posts are: choice of coronagraph, optimized wavefront control, observing strategy, and post-processing methods. After detailing each of the four foundations, we will present the lessons learned from the 10+ years of operations of zeroth and first-generation adaptive optics systems. We will then tentatively show how informative the current integration of second-generation adaptive optics system is, and which lessons can already be drawn from this fresh experience. Then, we will review the current state of the art, by presenting world record contrasts obtained in the framework of technological demonstrations for space-based exoplanet imaging and characterization mission concepts. Finally, we will conclude by emphasizing the importance of the cross-breeding between techniques developed for both ground-based and space-based projects, which is relevant for future high contrast imaging instruments and facilities in space or on the ground. © 2012 SPIE.
• Mayama, S., Hashimoto, J., Muto, T., Tsukagoshi, T., Kusakabe, N., Kuzuhara, M., Takahashi, Y., Kudo, T., Dong, R., Fukagawa, M., Takami, M., Momose, M., Wisniewski, J. P., Follette, K., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Carson, J., , Egner, S., et al. (2012). Subaru imaging of asymmetric features in a transitional disk in upper Scorpius. Astrophysical Journal Letters, 760(2).
  More info

  Abstract: We report high-resolution (0.07 arcsec) near-infrared polarized intensity images of the circumstellar disk around the star 2MASS J16042165-2130284 obtained with HiCIAO mounted on the Subaru 8.2m telescope. We present our H-band data, which clearly exhibit a resolved, face-on disk with a large inner hole for the first time at infrared wavelengths. We detect the centrosymmetric polarization pattern in the circumstellar material as has been observed in other disks. Elliptical fitting gives the semimajor axis, semiminor axis, and position angle (P.A.) of the disk as 63AU, 62AU, and -14°, respectively. The disk is asymmetric, with one dip located at P.A.s of ∼85°. Our observed disk size agrees well with a previous study of dust and CO emission at submillimeter wavelength with Submillimeter Array. Hence, the near-infrared light is interpreted as scattered light reflected from the inner edge of the disk. Our observations also detect an elongated arc (50AU) extending over the disk inner hole. It emanates at the inner edge of the western side of the disk, extending inward first, then curving to the northeast. We discuss the possibility that the inner hole, the dip, and the arc that we have observed may be related to the existence of unseen bodies within the disk. © 2012. The American Astronomical Society. All rights reserved.
• Mayama, S., Hashimoto, J., Muto, T., Tsukagoshi, T., Kusakabe, N., Kuzuhara, M., Takahashi, Y., Kudo, T., Dong, R., Fukagawa, M., Takami, M., Momose, M., Wisniewski, J., Follette, K., Abe, L., Akiyama, E., Brandner, W., Brandt, T., Carson, J., , Egner, S., et al. (2012). Subaru Imaging of Asymmetric Features in a Transitional Disk in Upper Scorpius. \apjl, 760(2), L26.
• McElwain, M. W., Brandt, T. D., Janson, M., Knapp, G. R., Peters, M. A., Burrows, A., Carlotti, A., Carr, M. A., Groff, T., Gunn, J. E., Guyon, O., Hayashi, M., Kasdin, N. J., Kuzuhara, M., Lupton, R. H., Martinache, F., Spiegel, D., Takato, N., Tamura, M., , Turner, E. L., et al. (2012). Scientific design of a high contrast integral field spectrograph for the Subaru telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8446.
  More info

  Abstract: Ground-based telescopes equipped with adaptive-optics (AO) systems and specialized science cameras are now capable of directly detecting extrasolar planets. We present the expected scientific capabilities of CHARIS, the Coronagraphic High Angular Resolution Imaging Spectrograph, which is being built for the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan. CHARIS will be implemented behind the new extreme adaptive optics system at Subaru, SCExAO, and the existing 188-actuator system AO188. CHARIS will offer three observing modes over near-infrared wavelengths from 0.9 to 2.4 μm (the y-, J-, H-, and K-bands), including a low-spectral-resolution mode covering this entire wavelength range and a high-resolution mode within a single band. With these capabilities, CHARIS will offer exceptional sensitivity for discovering giant exoplanets, and will enable detailed characterization of their atmospheres. CHARIS, the only planned high-contrast integral field spectrograph on an 8m-class telescope in the Northern Hemisphere, will complement the similar instruments such as Project 1640 at Palomar, and GPI and SPHERE in Chile. © 2012 SPIE.
• Minowa, Y., Hayano, Y., Terada, H., Pyo, T., Oya, S., Hattori, M., Shirahata, M., Takami, H., Guyon, O., Garrel, V., Colley, S., Weber, M., Golota, T., Watanabe, M., Saito, Y., Ito, M., & Iye, M. (2012). Subaru laser guide adaptive optics system: Performance and science operation. Proceedings of SPIE - The International Society for Optical Engineering, 8447.
  More info

  Abstract: The Subaru adaptive optics system (AO188) is a 188-element curvature sensor adaptive optics system that is operated in both natural and laser guide star modes. AO188 is installed at Nasmyth platform of the 8m Subaru telescope as a facility AO system. The laser guide star mode for AO188 has been commissioned and offered for use in science operation since 2011. The performance of AO188 in the laser guide star mode has been well verified from on-sky data obtained with the infrared camera and spectrograph (IRCS). In this paper, we describe the operation procedure and observing efficiency for the laser guide star mode. We also show the result of the on-sky performance evaluation of AO188 in the laser guide star mode and the characterization of the laser guide star, together with the obtained science results. © 2012 SPIE.
• Muto, T., Grady, C. A., Hashimoto, J., Fukagawa, M., Hornbeck, J. B., Sitko, M., Russell, R., Werren, C., Curé, M., Currie, T., Ohashi, N., Okamoto, Y., Momose, M., Honda, M., Inutsuka, S., Takeuchi, T., Dong, R., Abe, L., Brandner, W., , Brandt, T., et al. (2012). Discovery of small-scale spiral structures in the disk of SAO 206462 (HD135344B): Implications for the physical state of the disk from spiral density wave theory. Astrophysical Journal Letters, 748(2).
  More info

  Abstract: We present high-resolution, H-band imaging observations, collected with Subaru/HiCIAO, of the scattered light from the transitional disk around SAO 206462 (HD135344B). Although previous sub-mm imagery suggested the existence of a dust-depleted cavity at r ≤ 46 AU, our observations reveal the presence of scattered light components as close as 02 ( 28 AU) from the star. Moreover, we have discovered two small-scale spiral structures lying within 05 ( 70 AU). We present models for the spiral structures using the spiral density wave theory, and derive a disk aspect ratio of h 0.1, which is consistent with previous sub-mm observations. This model can potentially give estimates of the temperature and rotation profiles of the disk based on dynamical processes, independently from sub-mm observations. It also predicts the evolution of the spiral structures, which can be observable on timescales of 10-20 years, providing conclusive tests of the model. While we cannot uniquely identify the origin of these spirals, planets embedded in the disk may be capable of exciting the observed morphology. Assuming that this is the case, we can make predictions on the locations and, possibly, the masses of the unseen planets. Such planets may be detected by future multi-wavelength observations. © 2012. The American Astronomical Society. All rights reserved..
• Muto, T., Grady, C., Hashimoto, J., Fukagawa, M., Hornbeck, J., Sitko, M., Russell, R., Werren, C., Cur{\'e}, M., Currie, T., Ohashi, N., Okamoto, Y., Momose, M., Honda, M., Inutsuka, S., Takeuchi, T., Dong, R., Abe, L., Brandner, W., , Brandt, T., et al. (2012). Discovery of Small-scale Spiral Structures in the Disk of SAO 206462 (HD 135344B): Implications for the Physical State of the Disk from Spiral Density Wave Theory. \apjl, 748(2), L22.
• Narita, N., Takahashi, Y. H., Kuzuhara, M., Hirano, T., Suenaga, T., Kandori, R., Kudo, T., Sato, B., Suzuki, R., Ida, S., Nagasawa, M., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Egner, S. E., Feldt, M., Goto, M., Grady, C. A., , Guyon, O., et al. (2012). A Common Proper Motion Stellar Companion to HAT-P-7. \pasj, 64, L7.
• Narita, N., Takahashi, Y. H., Kuzuhara, M., Hirano, T., Suenaga, T., Kandori, R., Kudo, T., Sato, B., Suzuki, R., Ida, S., Nagasawa, M., Abe, L., Brandner, W., Brandt, T. D., Carson, J., Egner, S. E., Feldt, M., Goto, M., Grady, C. A., , Guyon, O., et al. (2012). A common proper motion stellar companion to HAT-P-7. Publications of the Astronomical Society of Japan, 64(6).
  More info

  Abstract: We report that HAT-P-7 has a common proper motion stellar companion. The companion is located at ̃3''009 to the east and estimated to be an M5.5V dwarf based on its colors. We also confirm the presence of a third companion, which was first reported byWinn et al. (2009, ApJ, 703, L99), based on long-term radial velocity measurements. We revisit the migration mechanism of HAT-P-7b given to the presence of those companions, and propose the sequential Kozai migration as a likely scenario in this system. This scenario may explain the reason for an outlier in the discussion of the spin-orbit alignment timescale for HAT-P-7b by Albrecht et al. (2012, ApJ, 757, 18). © 2012 Astronomical Society of Japan.
• Norris, B. R., Tuthill, P. G., Ireland, M. J., Lacour, S., Zijlstra, A. A., Lykou, F., Evans, T. M., Stewart, P., Bedding, T. R., Guyon, O., & Martinache, F. (2012). Probing dusty circumstellar environments with polarimetric aperture-masking interferometry. Proceedings of SPIE - The International Society for Optical Engineering, 8445.
  More info

  Abstract: Aperture-masking interferometry allows diffraction-limited images to be recovered despite the turbulent atmosphere. Here, this approach has been combined with polarimetry to form a novel technique allowing the dusty environments of mass-losing stars (so-called AGB stars) and proto-planetary and debris disks to be imaged, the characterisation of which is key to understanding the recycling of matter and the formation of new planetary systems. Polarimetric aperture-masking interferometry produces images by exploiting the fact that starlight scattered by circumstellar dust becomes strongly polarised. Essentially, aperture-masking allows access to the small spatial scales (∼10mas) necessary while polarimetry allows light from the dust and star to be differentiated. Furthermore, measurements at multiple wavelengths allow dust grain sizes to be calculated using Mie scattering theory. Excellent results have already been obtained at near-IR wavelengths using the NACO instrument at the VLT. The next step is to leverage the higher spatial resolution and polarisation signal found in the visible, rather than near-IR. To this end, a new instrument allowing precision polarimetric aperture masking interferometry at 600-800nm is being developed for an 8m class telescope, details of which will also be presented. © 2012 SPIE.
• Peters, M. A., Groff, T., Kasdin, N. J., McElwain, M. W., Galvin, M., Carr, M. A., Lupton, R., Gunn, J. E., Knapp, G., Gong, Q., Carlotti, A., Brandt, T., Janson, M., Guyon, O., Martinache, F., Hayashi, M., & Takato, N. (2012). Conceptual design of the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) for the Subaru telescope. Proceedings of SPIE - The International Society for Optical Engineering, 8446.
  More info

  Abstract: Recent developments in high-contrast imaging techniques now make possible both imaging and spectroscopy of planets around nearby stars. We present the conceptual design of the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), a lenslet-based, cryogenic integral field spectrograph (IFS) for imaging exo-planets on the Subaru telescope. The IFS will provide spectral information for 140x140 spatial elements over a 1.75 arcsecs x 1.75 arcsecs field of view (FOV). CHARIS will operate in the near infrared (λ = 0:9-2:5μm) and provide a spectral resolution of R = 14, 33, and 65 in three separate observing modes. Taking advantage of the adaptive optics systems and advanced coronagraphs (AO188 and SCExAO) on the Subaru telescope, CHARIS will provide sufficient contrast to obtain spectra of young self-luminous Jupiter-mass exoplanets. CHARIS is in the early design phases and is projected to have first light by the end of 2015. We report here on the current conceptual design of CHARIS and the design challenges. © 2012 SPIE.
• Tamura, M., Suto, H., Nishikawa, J., Kotani, T., Sato, B., Aoki, W., Usuda, T., Kurokawa, T., Kashiwagi, K., Nishiyama, S., Ikeda, Y., Hall, D., Hodapp, K., Hashimoto, J., Morino, J., Inoue, S., Mizuno, Y., Washizaki, Y., Tanaka, Y., , Suzuki, S., et al. (2012). Infrared Doppler instrument for the Subaru telescope (IRD). Proceedings of SPIE - The International Society for Optical Engineering, 8446.
  More info

  Abstract: IRD is the near-infrared high-precision radial velocity instrument for the Subaru 8.2-m telescope. It is a relatively compact (~1m size) spectrometer with a new echelle-grating and Volume-Phase Holographic gratings covering 1-2 micron wavelengths combined with an original frequency comb using optical pulse synthesizer. The spectrometer will employ a 4096x4096-pixel HgCdTe array under testing at IfA, University of Hawaii. Both the telescope/Adaptive Optics and comb beams are fed to the spectrometer via optical fibers, while the instrument is placed at the Nasmyth platform of the Subaru telescope. Expected accuracy of the Doppler-shifted velocity measurements is about 1 m s-1. Helped with the large collecting area and high image quality of the Subaru telescope, IRD can conduct systematic radial velocity surveys of nearby middle-to-late M stars aiming for down to one Earth-mass planet. Systematic observational and theoretical studies of M stars and their planets for the IRD science are also ongoing. We will report the design and preliminary development progresses of the whole and each component of IRD. © 2012 SPIE.
• Tanii, R., Itoh, Y., Kudo, T., Hioki, T., Oasa, Y., Gupta, R., Sen, A. K., Wisniewski, J. P., Muto, T., Grady, C. A., Hashimoto, J., Fukagawa, M., Mayama, S., Hornbeck, J., Sitko, M. L., Russell, R. W., Werren, C., Cure, M., Currie, T., , Ohashi, N., et al. (2012). High-resolution near-infrared polarimetry of a circumstellar disk around UXTauA. Publications of the Astronomical Society of Japan, 64(6).
  More info

  Abstract: We present H-band polarimetric imagery of UXTauA taken with HiCIAO/AO188 on the Subaru Telescope. UXTauA has been classified as a pre-transitional disk object, with a gap structure separating its inner and outer disks. Our imagery taken with the 0. ''15 (21AU) radius coronagraphic mask has revealed a strongly polarized circumstellar disk surrounding UXTauA, which extends to 120AU, at a spatial resolution of 0. ''1 (14AU). It is inclined by 46 ± 2, since the west side is nearest. Although SED modeling and sub-millimeter imagery have suggested the presence of a gap in the disk, with the inner edge of the outer disk estimated to be located at 25-30AU, we detect no evidence of a gap at the limit of our inner working angle (23AU) at the near-infrared wavelength. We attribute the observed strong polarization (up to 66%) to light scattering by dust grains in the disk. However, neither polarization models of the circumstellar disk based on Rayleigh-scattering nor Mie-scattering approximations were consistent with the observed azimuthal profile of the polarization degrees of the disk. Instead, a geometric optics model of the disk with nonspherical grains with radii of 30μm is consistent with the observed profile. We suggest that the dust grains have experienced frequent collisional coagulations, and have grown in the circumstellar disk of UXTauA. © 2012 Astronomical Society of Japan.
• Tanii, R., Itoh, Y., Kudo, T., Hioki, T., Oasa, Y., Gupta, R., Sen, A. K., Wisniewski, J. P., Muto, T., Grady, C. A., Hashimoto, J., Fukagawa, M., Mayama, S., Hornbeck, J., Sitko, M. L., Russell, R. W., Werren, C., Cur{\'e}, M., Currie, T., , Ohashi, N., et al. (2012). High-Resolution Near-Infrared Polarimetry of a Circumstellar Disk around UX Tau A. \pasj, 64, 124.
• Unwin, S., Traub, W., Bryden, G., Brugarolas, P., Chen, P., Guyon, O., Hillenbrand, L., Krist, J., MacIntosh, B., Mawet, D., Mennesson, B., Moody, D., Roberts Jr., L. C., Stapelfeldt, K., Stuchlik, D., Trauger, J., & Vasisht, G. (2012). Coronagraphic imaging of debris disks from a high altitude balloon platform. Proceedings of SPIE - The International Society for Optical Engineering, 8442.
  More info

  Abstract: Debris disks around nearby stars are tracers of the planet formation process, and they are a key element of our understanding of the formation and evolution of extrasolar planetary systems. With multi-color images of a significant number of disks, we can probe important questions: can we learn about planetary system evolution; what materials are the disks made of; and can they reveal the presence of planets? Most disks are known to exist only through their infrared flux excesses as measured by the Spitzer Space Telescope, and through images measured by Herschel. The brightest, most extended disks have been imaged with HST, and a few, such as Fomalhaut, can be observed using ground-based telescopes. But the number of good images is still very small, and there are none of disks with densities as low as the disk associated with the asteroid belt and Edgeworth- Kuiper belt in our own Solar System. Direct imaging of disks is a major observational challenge, demanding high angular resolution and extremely high dynamic range close to the parent star. The ultimate experiment requires a space-based platform, but demonstrating much of the needed technology, mitigating the technical risks of a space-based coronagraph, and performing valuable measurements of circumstellar debris disks, can be done from a high-altitude balloon platform. In this paper we present a balloon-borne telescope concept based on the Zodiac II design that could undertake compelling studies of a sample of debris disks. © 2012 SPIE.
• Ammons, S. M., Bendek, E. A., & Guyon, O. (2011). Microarcsecond relative astrometry from the ground with a diffractive pupil. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: The practical use of astrometry to detect exoplanets via the reflex motion of the parent star depends critically on the elimination of systematic noise floors in imaging systems. In the diffractive pupil technique proposed for space-based detection of exo-earths, extended diffraction spikes generated by a dotted primary mirror are referenced against a widefield grid of background stars to calibrate changing optical distortion and achieve microarcsecond astrometric precision on bright targets (Guyon et al. 2010). We describe applications of this concept to ground-based uncrowded astrometry using a diffractive, monopupil telescope and a wide-field camera to image as many as ∼4000 background reference stars. Final relative astrometric precision is limited by differential tip/tilt jitter caused by high altitude layers of turbulence. A diffractive 3-meter telescope is capable of reaching ∼35 μas relative astrometric error per coordinate perpendicular to the zenith vector in three hours on a bright target star (I < 10) in fields of moderate stellar density (∼40 stars arcmin-2 with I < 23). Smaller diffractive apertures (D < 1 m) can achieve 100-200 μas performance with the same stellar density and exposure time and a large telescope (6.5-10 m) could achieve as low as 10 μas, nearly an order of magnitude better than current space-based facilities. The diffractive pupil enables the use of larger fields of view through calibration of changing optical distortion as well as brighter target stars (V < 6) by preventing star saturation. Permitting the sky to naturally roll to average signals over many thousands of pixels can mitigate the effects of detector imperfections. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Balasubramanian, K., Cady, E., Pueyo, L., Xin, A. n., Shaklan, S., Guyon, O., & Belikov, R. (2011). Diamond turned high precision PIAA optics and four mirror PIAA system for high contrast imaging of exo-planets. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: Off-axis, high-sag PIAA optics for high contrast imaging present challenges in manufacturing and testing. With smaller form factors and consequently smaller surface deformations (< 80 microns), diamond turned fabrication of these mirrors becomes feasible. Though such a design reduces the system throughput, it still provides 2λ/D inner working angle. We report on the design, fabrication, measurements, and initial assessment of the novel PIAA optics in a coronagraph testbed. We also describe, for the first time, a four mirror PIAA coronagraph that relaxes apodizer requirements and significantly improves throughput while preserving the low-cost benefits. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Belikov, R., Pluzhnik, E., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., & Guyon, O. (2011). Laboratory demonstration of high-contrast imaging at inner working angles 2 λ/D and better. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: Coronagraph technology is advancing and promises to enable direct imaging and spectral characterization of extrasolar Earth-like planets in the 2020 decade with a telescope as small as 1.5m. A small Explorer-sized telescope can also be launched in the 2010 decade capable of seeing debris disks as dim as tens of zodis and potentially a few large planets. The Phase Induced Amplitude Apodization (PIAA) coronagraph makes such aggressive performance possible, providing high throughput and high contrast close to the diffraction limit. We report on the latest results from a testbed at NASA Ames that is focused on developing and testing the PIAA coronagraph. This laboratory facility was built in 2008 and is designed to be flexible, operated in an actively thermally stabilized air environment, and to complement collaborative efforts at NASA JPL's High Contrast Imaging Testbed. For our wavefront control we are using small Micro-Electro- Mechanical-System deformable mirrors (MEMS DMs), which promise to reduce the size of the beam and overall instrument, a consideration that becomes very important for small telescopes. We describe our lab progress and results, which include (as of August 2011): the demonstration of 1.9x10 -8 average raw contrast in a dark zone from 2.0 - 3.4 λ/D and of 1.2x10-6 contrast from 1.5-2.0 λ/D (in monochromatic light); the testing of the next-generation reflective PIAA mirror set built by Tinsley and designed for broadband; and finally, discuss our most important past limiting factors as well as expected future ones. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Bendek, E. A., Ammons, S. M., Shankar, H., & Guyon, O. (2011). Dynamic distortion calibration using a diffracting pupil: High precision astrometry laboratory demonstration for exoplanet detection. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: Detection of earth-size exoplanets using the astrometric signal of the host star requires sub microarcsecond measurement precision. One major challenge in achieving this precision using a medium-size (
• Blain, C., Guyon, O., Bradley, C., & Lardière, O. (2011). Fast iterative algorithm (FIA) for controlling MEMS deformable mirrors: Principle and laboratory demonstration. Optics Express, 19(22), 21271-21294.
  More info

  PMID: 22108979;Abstract: We present a fast and high accuracy iterative algorithm to control Micro-Electro-Mechanical-System (MEMS) deformable mirrors (DMs) for open-loop (OL) adaptive optics (AO) applications. Our approach relies on a simple physical model for the forces applied on DM actuators and membrane, defined by a small number of parameters that we measure in an experimental setup. The algorithm iteratively applies forces and updates actuator displacements, allowing real-time utilization in an Extreme-AO system (control rate ≥ Khz). Our measurements show that it reproduces Kolmogorov type phase screens with an error equal to 7.3% of the rms of the desired phase (1.6% of the peak-to-valley of the desired phase). This performance corresponds to an improvement of a factor three compared to the standard quadratic model (common relation between voltage and actuator displacement). Originally developed for the DM control of the Subaru Coronagraphic Extreme-AO (SCExAO) project, the algorithm is also suitable for Multi-Object AO systems. © 2011 Optical Society of America.
• Enya, K., Kotani, T., Haze, K., Aono, K., Nakagawa, T., Matsuhara, H., Kataza, H., Wada, T., Kawada, M., Fujiwara, K., Mita, M., Takeuchi, S., Komatsu, K., Sakai, S., Uchida, H., Mitani, S., Yamawaki, T., Miyata, T., Sako, S., , Nakamura, T., et al. (2011). The SPICA coronagraphic instrument (SCI) for the study of exoplanets. Advances in Space Research, 48(2), 323-333.
  More info

  Abstract: We present the SPICA Coronagraphic Instrument (SCI), which has been designed for a concentrated study of extra-solar planets (exoplanets). SPICA mission provides us with a unique opportunity to make high contrast observations because of its large telescope aperture, the simple pupil shape, and the capability for making infrared observations from space. The primary objectives for the SCI are the direct coronagraphic detection and spectroscopy of Jovian exoplanets in infrared, while the monitoring of transiting planets is another important target. The specification and an overview of the design of the instrument are shown. In the SCI, coronagraphic and non-coronagraphic modes are aplicable for both an imaging and a spectroscopy. The core wavelength range and the goal contrast of the coronagraphic mode are 3.5-27 μm, and 10 -6, respectively. Two complemental designs of binary shaped pupil mask coronagraph are presented. The SCI has capability of simultaneous observations of one target using two channels, a short channel with an InSb detector and a long wavelength channel with a Si:As detector. We also give a report on the current progress in the development of key technologies for the SCI. © 2011 COSPAR. Published by Elsevier Ltd. All rights reserved. 31.
• Garrel, V., Guyon, O., Baudoz, P., Martinache, F., Stewart, P., Lozi, J., & Groff, T. (2011). The Subaru coronagraphic extreme AO (SCExAO) system: Fast visible imager. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system is an instrument designed to be inserted between the Subaru AO188 system and the infrared HiCIAO camera in order to greatly improve the contrast in the very close (less than 0.5″) neighbourhood of stars.Next to the infrared coronagraphic path, a visible scientific path, based on a EMCCD camera, has been implemented. Benefiting from both AO correction and new data processing techniques, it is a powerful tool for high angular resolution imaging and opens numerous new science opportunities. A factor 2 to 3 in Strehl ratio is obtained compared to the AO long exposure time: up to 25% Strehl in the 650nm wavelength, depending on the image processing algorithm used and the seeing conditions. The system is able to deliver diffraction limited images at 650 nm (17 mas FWHM). Our baseline image processing algorithm is based on the selection of the best signal for each spatial frequency. We demonstrate that this approach offers significantly better results than the classical select, shift and add approach (lucky imaging). © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Guyon, O., & Martinache, F. (2011). Achieving high-precision ground-based photometry for transiting exoplanets. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: Detection of transiting exoplanets requires high precision photometry, at the percent level for giant planets and at the 1e-5 level for detection of Earth-like rocky planets. Space provides an ideally stable - but costly - environment for high precision photometry. Achieving high precision photometry on a large number of sources from the ground is scientifically valuable, but also very challenging, due to multiple sources of errors. These errors can be greatly reduced if a large number of small wide field telescopes is used with an adequate data analysis algorithm, and the recent availability of low cost high performance digital single lens reflex (DSLR) cameras thus provides an interesting opportunity for exoplanet transit detection. We have recently assembled a prototype DSLR-based robotic imaging system for astronomy, showing that robotic high imaging quality units can be build at a small cost (under $10000 per deg2m2 of etendue), allowing multiple units to be built and operated. We demonstrate that a newly developed data reduction algorithm can overcome detector sampling and color issues, and allow precision photometry with these systems, approaching the limit set by photon noise and scintillation noise - which can both average as the inverse square root of etendue. We conclude that for identification of a large number of exoplanets, a ground-based distributed system consisting of a large number of DSLR-based units is a scientifically valuable cost-effective approach. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Guyon, O., Bendek, E., Ammons, M., Shao, M., Shaklan, S., Woodruff, R. A., & Belikov, R. (2011). Diffractive pupil telescope for high precision space astrometry. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: A concept for high precision astrometry with a conventional wide field telescope is presented, enabling a space telescope to perform simultaneously coronagraphic imaging of exoplanets, astrometric measurement of their orbits and masses, and deep wide field imaging for a wide range of astrophysical investigations. Our concept uses a diffractive telescope pupil (primary mirror), obtained by placing a regular grid of small sub millimeter spots on the primary mirror coating. When the telescope is pointed at a bright star, the wide field image contains both a large number of background stars used for astrometric referencing, and faint diffraction spikes created by the grid of dots on the primary mirror. The diffraction spikes encode instrumental astrometric distortions due to optics or the detector, allowing precise measurement of the central star against a large number of faint background stars. With up to a few percent of the primary mirror area covered by the dots, the fraction of the central starlight located in the diffraction spikes is kept sufficiently small to allow full sensitivity deep imaging over the telescope's field of view. Since the dots are regularly spaced, they do not diffract light at small angular separations, and therefore allow full coronagraphic imaging capability. We show that combining simultaneous astrometric and coronagraphic measurements allows improved detection and characterization of exoplanets by constraining the planet(s) characteristics with both measurements. Our preliminary astrometric accuracy error budget shows that sub-micro arcsecond astrometry can be achieved with a 1.4 m diameter telescope, and that astrometric accuracy improves rapidly with telescope diameter. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Guyon, O., Kern, B., Belikov, R., Shaklan, S., Kuhnert, A., & Give'on, A. (2011). Phase-Induced Amplitude Apodization (PIAA) coronagraphy: Recent results and future prospects. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: The Phase Induced Amplitude Apodization (PIAA) concept uses aspheric optics to apodize a telescope beam for high contrast imaging. The lossless apodization, achieved through geometrical redistribution of the light (beam shaping) allows designs of high performance coronagraphs, ideally suited for direct imaging of exoplanets similar to Earth around nearby stars. The PIAA coronagraph concept has evolved since its original formulation to mitigate manufacturing challenges and improve performance. Our group is currently aiming at demonstrating PIAA coronagraphy in the laboratory to 1e-9 raw contrast at 2 λ/D separation. Recent results from the High Contrast Imaging Testbed (HCIT) at NASA JPL and the PIAA testbed at NASA Ames demonstrate contrasts about one order of magnitude from this goal at 2 λ/D. In parallel with our high contrast demonstration at 2λ/D, we are developing and testing new designs at a complementary testbed at NASA Ames, and solving associated technical challenges. Some of these new PIAA designs have been tested that can further mitigate PIAA manufacturing challenges while providing theoretically total starlight extinction and offering 50% throughput at less than 1 λ/D. Recent tests demonstrated on the order of 1e-6 contrast close to 1 λ/D (while maintaining 5e-8 contrast at 2 λ/D). © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Guyon, O., Martinache, F., Clergeon, C., Russell, R., Groff, T., & Garrel, V. (2011). Wavefront control with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system. Proceedings of SPIE - The International Society for Optical Engineering, 8149.
  More info

  Abstract: The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system uses advanced coronagraphic technique for high contrast imaging of exoplanets and disks as close as 1 lambda/D from the host star. In addition to unusual optics, achieving high contrast at this small angular separation requires a wavefront sensing and control architecture which is optimized for exquisite control and calibration of low order aberrations. The SCExAO system was thus designed to include the wavefront sensors required for bias-free high sensitivity and high speed wavefront measurements. Information is combined from two infrared wavefront sensors and a fast visible wavefront sensors to drive a single MEMS type deformable mirror mounted on a tip-tilt mount. The wavefront sensing and control architecture is highly integrated with the coronagraph system. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Hashimoto, J., Tamura, M., Muto, T., Kudo, T., Fukagawa, M., Fukue, T., Goto, M., Grady, C. A., Henning, T., Hodapp, K., Honda, M., Inutsuka, S., Kokubo, E., Knapp, G., McElwain, M. W., Momose, M., Ohashi, N., Okamoto, Y. K., Takami, M., , Turner, E. L., et al. (2011). Direct imaging of fine structures in giant planet-forming regions of the protoplanetary disk around AB Aurigae. Astrophysical Journal Letters, 729(2 PART II).
  More info

  Abstract: We report high-resolution 1.6 μm polarized intensity (PI) images of the circumstellar disk around the Herbig Ae star AB Aur at a radial distance of 22 AU (015) up to 554 AU (385), which have been obtained by the high-contrast instrument HiCIAO with the dual-beam polarimetry. We revealed complicated and asymmetrical structures in the inner part (≲140 AU) of the disk while confirming the previously reported outer (r ≳ 200 AU) spiral structure. We have imaged a double ring structure at 40 and 100 AU and a ring-like gap between the two. We found a significant discrepancy of inclination angles between two rings, which may indicate that the disk of AB Aur is warped. Furthermore, we found seven dips (the typical size is 45 AU or less) within two rings, as well as three prominent PI peaks at 40 AU. The observed structures, including a bumpy double ring, a ring-like gap, and a warped disk in the innermost regions, provide essential information for understanding the formation mechanism of recently detected wide-orbit (r > 20 AU) planets. © 2011. The American Astronomical Society. All rights reserved.
• Hashimoto, J., Tamura, M., Muto, T., Kudo, T., Fukagawa, M., Fukue, T., Goto, M., Grady, C., Henning, T., Hodapp, K., Honda, M., Inutsuka, S., Kokubo, E., Knapp, G., McElwain, M., Momose, M., Ohashi, N., Okamoto, Y., Takami, M., , Turner, E., et al. (2011). Direct Imaging of Fine Structures in Giant Planet-forming Regions of the Protoplanetary Disk Around AB Aurigae. \apjl, 729(2), L17.
• Janson, M., Carson, J., Thalmann, C., McElwain, M. W., Goto, M., Crepp, J., Wisniewski, J., Abe, L., Brandner, W., Burrows, A., Egner, S., Feldt, M., Grady, C. A., Golota, T., Guyon, O., Hashimoto, J., Hayano, Y., Hayashi, M., Hayashi, S., , Henning, T., et al. (2011). Near-infrared multi-band photometry of the substellar companion GJ 758 B. Astrophysical Journal, 728(2).
  More info

  Abstract: GJ 758 B is a cold (∼600 K) companion to a Sun-like star at 29 AU projected separation, which was recently detected with high-contrast imaging. Here, we present photometry of the companion in seven photometric bands from Subaru/HiCIAO, Gemini/NIRI, and Keck/NIRC2, providing a rich sampling of the spectral energy distribution in the 1-5 μm wavelength range. A clear detection at 1.58 μm combined with an upper limit at 1.69 μm shows methane absorption in the atmosphere of the companion. The mass of the companion remains uncertain, but an updated age estimate indicates that the most likely mass range is ∼30-40 Mjup. In addition, we present an updated astrometric analysis that imposes tighter constraints on GJ 758 B's orbit and identifies the proposed second candidate companion, "GJ 758 C," as a background star. © 2011. The American Astronomical Society. All rights reserved. Printedin the U.S.A.
• Janson, M., Carson, J., Thalmann, C., McElwain, M., Goto, M., Crepp, J., Wisniewski, J., Abe, L., Brandner, W., Burrows, A., Egner, S., Feldt, M., Grady, C., Golota, T., Guyon, O., Hashimoto, J., Hayano, Y., Hayashi, M., Hayashi, S., , Henning, T., et al. (2011). Near-infrared Multi-band Photometry of the Substellar Companion GJ 758 B. \apj, 728(2), 85.
• Kern, B., Guyon, O., Give'on, A., Kuhnert, A., & Niessner, A. (2011). Laboratory testing of a Phase-Induced Amplitude Apodization (PIAA) coronagraph. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: We present high-contrast images from laboratory testing of a Phase Induced Amplitude Apodization (PIAA) coronagraph at NASA's High Contrast Imaging Testbed (HCIT). Using a deformable mirror and wavefront estimation and control algorithms, we create a "dark hole" in the monochromatic point-spread function with an inner working angle of 2.05 fλ/D, with a mean intensity 3.5×10-8. We discuss the contributions to this floor, and the techniques being developed to improve it. We also present simulations that investigate the effect of Lyot stops of various sizes, and conclude that a Lyot stop is necessary for 10-9 performance but that an annular postapodizer is not necessary. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Martinache, F., Guyon, O., Garrel, V., Clergeon, C., Groff, T., Stewart, P., Russell, R., & Blain, C. (2011). The Subaru coronagraphic extreme AO project: Progress report. Proceedings of SPIE - The International Society for Optical Engineering, 8151.
  More info

  Abstract: In 2009 our group started the integration of the SCExAO project, a highly flexible, open platform for high contrast imaging at the highest angular resolution, inserted between the coronagraphic imaging camera HiCIAO and the 188-actuator AO system of Subaru. In its first version, SCExAO combines a MEMS-based wavefront control system feeding a high performance PIAA-based coronagraph. It also includes a coronagraphic low-order wavefront sensor, a non-redundant aperture mask and a visible imaging mode, all of them designed to take full advantage of the angular resolution that an 8-meter telescope has to offer. SCExAO is currently undergoing commissioning, and this paper presents the first on-sky results acquired in August 2011, using together Subaru's AO system, SCExAO and HiCIAO. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• Mateen, M., Guyon, O., Sasián, J., Garrel, V., & Hart, M. (2011). The non-linear curvature wavefront sensor reconstruction speed and the broadband design. Proceedings of SPIE - The International Society for Optical Engineering, 8149.
  More info

  Abstract: In this paper we explain why a non-linear curvature wavefront sensor (nlCWFS) is more sensitive than conventional wavefront sensors such as the Shack Hartmann wavefront sensor (SHWFS) and the conventional curvature wavefront sensor (cCWFS) for sensing mV < 14 natural guide stars. The non-linear approach builds on the successful curvature wavefront sensing concept but uses a non-linear Gerchberg-Saxton (GS) phase diversity algorithm to reconstruct the wavefront. The nonlinear reconstruction algorithm is an advantage for sensitivity but a challenge for fast computation. The current speed is a factor of 10 to 100 times slower than needed for high performance groundbased AO. We present a two step strategy to increase the speed of the algorithm. In the last paper3 we presented laboratory results obtained with a monochromatic source, here we extend our experiment to incorporate a broadband source. The sensitivity of the nlCWFS depends on the ability to extract wavefront phase from diffraction limited speckles therefore it is essential that the speckles do not suffer from chromatic aberration when used with a polychromatic source. We discuss the design for the chromatic re-imaging optics, which through chromatic compensation, allow us to obtain diffraction limited speckles in Fresnel propagated planes on either side of the pupil plane. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
• P., F., Martinache, F., Guyon, O., Yoshikawa, T., Yokochi, K., Garrel, V., & Matsuo, T. (2011). Coronagraphic low-order wavefront sensor: Postprocessing sensitivity enhancer for high-performance coronagraphs. Publications of the Astronomical Society of the Pacific, 123(910), 1434-1441.
  More info

  Abstract: Detection and characterization of exoplanets by direct imaging requires a coronagraph designed to deliver high-contrast at small angular separation. To achieve this, an accurate control of low-order aberrations, such as pointing and focus errors, is essential to optimize coronagraphic rejection and avoid the possible confusion between exoplanet light and coronagraphic leaks in the science image. Simulations and laboratory prototyping have shown that a coronagraphic low-order wavefront sensor (CLOWFS), using a single defocused image of a reflective focal-plane ring, can be used to control tip-tilt to an accuracy of 10 _3 λ=D. This article demonstrates that the data acquired by CLOWFS can also be used in postprocessing to calibrate residual coronagraphic leaks from the science image. Using both the CLOWFS camera and the science camera in the system, we quantify the accuracy of the method and its ability to successfully remove light due to low-order errors from the science image. We also report the implementation and performance of the CLOWFS on the Subaru Coronagraphic Extreme-AO (SCExAO) system and its expected on-sky performance. In the laboratory, with a level of disturbance similar to that encountered in a post-AO beam, CLOWFS postprocessing has achieved speckle calibration to 1=300 of the raw speckle level. This is about 40 times better than could be done with an idealized PSF subtraction that does not rely on CLOWFS. © 2011. The Astronomical Society of the Pacific. All rights reserved.
• Thalmann, C., Janson, M., Buenzli, E., Brandt, T. D., Wisniewski, J. P., Moro-Martín, A., Usuda, T., Schneider, G., Carson, J., McElwain, M. W., Grady, C. A., Goto, M., Abe, L., Brandner, W., Dominik, C., Egner, S., Feldt, M., Fukue, T., Golota, T., , Guyon, O., et al. (2011). Images of the extended outer regions of the debris ring around HR 4796 A. Astrophysical Journal Letters, 743(1).
  More info

  Abstract: We present high-contrast images of HR 4796 A taken with Subaru/HiCIAO in the H band, resolving the debris disk in scattered light. The application of specialized angular differential imaging methods allows us to trace the inner edge of the disk with high precision and reveals a pair of "streamers" extending radially outward from the ansae. Using a simple disk model with a power-law surface brightness profile, we demonstrate that the observed streamers can be understood as part of the smoothly tapered outer boundary of the debris disk, which is most visible at the ansae. Our observations are consistent with the expected result of a narrow planetesimal ring being ground up in a collisional cascade, yielding dust with a wide range of grain sizes. Radiation forces leave large grains in the ring and push smaller grains onto elliptical or even hyperbolic trajectories. We measure and characterize the disk's surface brightness profile, and confirm the previously suspected offset of the disk's center from the star's position along the ring's major axis. Furthermore, we present first evidence for an offset along the minor axis. Such offsets are commonly viewed as signposts for the presence of unseen planets within a disk's cavity. Our images also offer new constraints on the presence of companions down to the planetary mass regime (∼9 M Jup at 0″.5, ∼3M Jup at 1″). © 2011. The American Astronomical Society. All rights reserved.
• Thalmann, C., Janson, M., Buenzli, E., Brandt, T., Wisniewski, J., Moro-Mart{\'\in}, A., Usuda, T., Schneider, G., Carson, J., McElwain, M., Grady, C., Goto, M., Abe, L., Brandner, W., Dominik, C., Egner, S., Feldt, M., Fukue, T., Golota, T., , Guyon, O., et al. (2011). Images of the Extended Outer Regions of the Debris Ring around HR 4796 A. \apjl, 743(1), L6.
• Vogt, F. P., Martinache, F., Guyon, O., Yoshikawa, T., Yokochi, K., Garrel, V., & Matsuo, T. (2011). Coronagraphic Low-Order Wavefront Sensor: Postprocessing Sensitivity Enhancer for High-Performance Coronagraphs. \pasp, 123(910), 1434.
• Balasubramanian, K., Shaklan, S. B., Pueyo, L., Wilson, D. W., & Guyon, O. (2010). Low-cost high-precision PIAA optics for high contrast imaging with exo-planet coronagraphs. Proceedings of SPIE - The International Society for Optical Engineering, 7731.
  More info

  Abstract: PIAA optics for high contrast imaging present challenges in manufacturing and testing due to their large surface departures from aspheric profiles at the aperture edges. With smaller form factors and consequent smaller surface deformations (
• Belikova, R., Pluzhnik, E., Connelley, M. S., Witteborn, F. C., Greeun, T. P., Lynch, D. H., Zell, P. T., & Guyon, O. (2010). Laboratory demonstration of high-contrast imaging at 2 λ/D on a temperature-stabilized testbed in air. Proceedings of SPIE - The International Society for Optical Engineering, 7731.
  More info

  Abstract: Direct imaging of extrasolar planets in visible light, and Earth-like planets in particular, is an exciting but difficult problem requiring a telescope imaging system with 10-10 contrast at separations of l00mas and less. Furthermore, only a small 1-2m space telescope may be realistic for a mission in the foreseeable future, which puts strong demands on the performance of the imaging instrument. Fortunately, an efficient coronagraph called the Phase Induced Amplitude Apodization (PIAA) coronagraph may enable Earth-like planet imaging for such small telescopes if any exist around the nearest stars. In this paper, we report on the latest results from a testbed at the NASA Ames Research Center focused on testing the PIAA coronagraph. This laboratory facility was built in 2008 and is designed to be flexible, operated in a highly stabilized air environment, and to complement efforts at NASA JPL's High Contrast Imaging Testbed. For our wavefront control we are focusing on using small Micro-Electro-Mechanical-System deformable minors (MEMS DMs), which promises to reduce the size of the beam and overall instrument, a consideration that becomes very important for small telescopes. In this paper, we briefly describe our lab and methods, including the new active thermal control system, and report the demonstration of 5.4×l0-8 average raw contrast in a dark zone from 2.0 - 5.2 λ/D. In addition, we present an analysis of our current limits and solutions to overcome them. © 2010 SPIE.
• Blain, C., Conan, R., Bradley, C., & Guyon, O. (2010). Open-loop control demonstration of Micro-Electro-Mechanical-System MEMS deformable mirror. Optics Express, 18(6), 5433-5448.
  More info

  PMID: 20389560;Abstract: New astronomical challenges revolve around the observation of faint galaxies, nearby star-forming regions and the direct imaging of exoplanets. The technologies required to progress in these fields of research rely on the development of custom Adaptive Optics (AO) instruments such as Multi-Object AO (MOAO) or Extreme AO (ExAO). Many obstacles remain in the development of these new technologies. A major barrier to the implementation of MOAO is the utilisation of deformable mirrors (DMs) in an open-loop control system. Micro-Electro-Mechanical-System (MEMS) DMs show promise for application in both MOAO and ExAO. Despite recent encouraging laboratory results, it remains an immature technology which has yet to be demonstrated on a fully operational on-sky AO system. Much of the research in this area focuses on the development of an accurate model of the MEMS DMs. In this paper, a thorough characterization process of a MEMS DM is performed, with the goal of developing an open-loop control strategy free of computationally heavy modelling (such as the use of plate equations). Instead, a simpler approach, based on the additivity of the influence functions, is chosen. The actuator stroke-voltage relationship and the actuator influence functions are carefully calibrated. For 100 initial phase screens with a mean rms of 97 nm (computer generated following a Von Karman statistic), the resulting mean residual open-loop rms error is 16.5 nm, the mean fitting error rms is 13.3 nm and the mean DM error rms is 10.8 nm (error reflecting the performances of the model under test in this paper). This corresponds to 11% of residual DM error. © 2010 Optical Society of America.
• Blain, C., Conan, R., Bradley, C., Guyon, O., Gamroth, D., & Nash, R. (2010). Real-time open-loop control of a 1024-actuator MEMS deformable mirror. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: This article reports the progress made at the University of Victoria AO Lab, regarding the realtime open-loop control of a 1024-actuator MEMS deformable mirror (DM). The setup is an hybrid woofer-tweeter/open-loop bench. A tip-tilt mirror and a woofer DM (a 57-actuator CILAS DM) are driven in closed-loop while a 1024-actuator MEMS DM is utilized on a parallel open-loop path. Previous work shows that open-loop control providing low residual error (with frozen Kolmogorov turbulence) can be obtained without the need of DM modelling. A preliminary methodical calibration of the DM is employed instead. The MEMS electronics were upgraded to an update rate of 500 Hz and the experiment lays the groundwork for showing how these performances can also be achieved on the bench with dynamic turbulence (created with custom hot air turbulence generators). The current status of the experiment and the next milestones are presented. © 2010 SPIE.
• Garrei, V., Guyon, O., Baudoz, P., Martinache, F., Vogt, F., Takashi, Y., Kaito, Y., & Cantalloube, F. (2010). The Subaru coronagraphic extreme AO (SCExAO) system: Visible imaging mode. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system is an instrument designed to be inserted between the Subaru AO188 system and the infrared HiCIAO camera in order to greatly improve the contrast in the very close (less than 0.5") neighbourhood of stars. Next to the infrared coronagraphic path, a visible scientific path, based on a EMCCD camera, has been implemented. Benefiting from both Adaptive Optics (AO) correction and new data processing techniques, it is a powerful tool for high angular resolution imaging and opens numerous new science opportunities. We propose here a new image processing algorithm, based on the selection of the best signal for each spatial frequency. A factor 2 to 3 in Střehl ratio is obtained compared to the AO long exposure time depending on the image processing algorithm used and the seeing conditions. The system is able to deliver diffraction limited images at 650 nm (17 mas FWHM).We also demonstrate that this approach offers significantly better results than the classical select, shift and add approach (lucky imaging). © 2010 SPIE.
• Guyon, O. (2010). High Sensitivity Wavefront Sensing with a Nonlinear Curvature Wavefront Sensor. \pasp, 122(887), 49.
• Guyon, O., Martinache, F., Belikov, R., & Soummer, R. (2010). High Performance PIAA Coronagraphy with Complex Amplitude Focal Plane Masks. \apjs, 190(2), 220-232.
• Guyon, O., Martinache, F., Belikov, R., & Soummer, R. (2010). High performance piaa coronagraphy with complex amplitude focal plane masks. Astrophysical Journal, Supplement Series, 190(2), 220-232.
  More info

  Abstract: We describe a coronagraph approach where the performance of a Phase-Induced Amplitude Apodization (PIAA) coronagraph is improved by using a partially transmissive phase-shifting focal plane mask and a Lyot stop. This approach combines the low inner working angle offered by phase mask coronagraphy, the full throughput and uncompromized angular resolution of the PIAA approach, and the design flexibility of Apodized Pupil Lyot Coronagraph. A PIAA complex mask coronagraph (PIAACMC) is fully described by the focal plane mask size, or, equivalently, its complex transmission which ranges from 0 (opaque) to -1 (phase shifting). For all values of the transmission, the PIAACMC theoretically offers full on-axis extinction and 100% throughput at large angular separations. With a pure phase focal plane mask (complex transmission = -1), the PIAACMC offers 50% throughput at 0.64 λ/D while providing total extinction of an on-axis point source. This performance is very close to the "fundamental performance limit" of coronagraphy derived from first principles. For very high contrast level, imaging performance with PIAACMC is in practice limited by the angular size of the on-axis target (usually a star). We show that this fundamental limitation must be taken into account when choosing the optimal value of the focal plane mask size in the PIAACMC design. We show that the PIAACMC enables visible imaging of Jupiter-like planets at ≈1.2 λ/D from the host star, and can therefore offer almost three times more targets than a PIAA coronagraph optimized for this type of observation. We find that for visible imaging of Earthlike planets, the PIAACMC gain over a PIAA is probably much smaller, as coronagraphic performance is then strongly constrained by stellar angular size. For observations at "low" contrast (below ≈108), the PIAACMC offers significant performance enhancement over PIAA. This is especially relevant for ground-based high contrast imaging systems in the near-IR, where PIAACMC enables high contrast high efficiency imaging within 1 λ/D. Manufacturing tolerances for the focal plane mask are quantified for a few representative PIAACMC designs. © 2010. The American Astronomical Society. All rights reserved.
• Guyon, O., Martinache, F., Garrel, V., Vogt, F., Yokochi, K., & Yoshikawa, T. (2010). The subaru coronagraphic extreme AO (SCExAO) system: Wavefront control and detection of exoplanets with coherent light modulation in the focal plane. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: The Subaru Coronagraphic Extreme-AO (SCExAO) system is designed for high contrast coronagraphic imaging at small angular separations, and is scheduled to see first light on the Subam Telescope in early 2011. The wavefront control architecture for SCExAO is optimized for scattered light control and calibration at small angular separations, and is described in this paper. Key subsystems for the SCExAO wavefront control architecture have been successfully demonstrated, and we report results from these tests and discuss their role in the SCExAO system. Among these subsystems, a technique which can calibrate and remove static and slow speckles which traditionally limit high contrast detections is discussed. A visible light lab prototype system at Subam Telescope recently demonstrated speckle halo reduction to 2e-7 contrast within 2 λ/D, and removal of static coherent speckles to 3e-9 contrast. © 2010 SPIE.
• Guyon, O., Pluzhnik, E., Martinache, F., Totems, J., Tanaka, S., Matsuo, T., Blain, C., & Belikov, R. (2010). High-Contrast Imaging and Wavefront Control with a PIAA Coronagraph: Laboratory System Validation. \pasp, 122(887), 71.
• Guyon, O., Shaklan, S., Levine, M., Cahoy, K., Tenerelli, D., Belikov, R., & Kern, B. (2010). The Pupil mapping Exoplanet Coronagraphic Observer. Proceedings of SPIE - The International Society for Optical Engineering, 7731.
  More info

  Abstract: The Pupil-mapping Exoplanet Coronagraphic Observer (PECO) mission concept is a 1.4-m space-based coronagraphic telescope optimized to image exoplanets and disks at optical wavelengths and characterize them through low resolution spectroscopy and polarimetry. Thanks to a high efficiency Phase-Induced Amplitude Apodization (PIAA) coronagraph, PECO can deliver 1e-10 contrast at 2 λ/D separation (0.15″) with no loss in angular resolution or throughput due to the coronagraph. PECO acquires narrow field images simultaneously in 16 spectral bands over wavelengths from 0.4 to 0.9 urn, utilizing all available photons for maximum wavefront sensing efficiency and optimal sensitivity for imaging and spectroscopy. PECO can detect and characterize potentially habitable planets around 20 known F, G, K type stars, and map exozodiacal clouds to a fraction of our own own zodiacal dust content. PECO's key technologies are currently under active development at several testbeds, and will enable efficient exoplanet imaging missions across a wide range of telescope sizes, from a sub-meter debris disk and giant planet imager to a ∼4-m life-finding mission. © 2010 SPIE.
• Guyon, O., Shao, M., Shaklan, S., Levine, M., Amnions, M., Bendek, E., Woodruff, R., Nemati, B., & Pitman, J. (2010). Single aperture imaging astrometry with a diffracting pupil: Application to exoplanet mass measurement with a small coronagraphic space telescope. Proceedings of SPIE - The International Society for Optical Engineering, 7731.
  More info

  Abstract: High precision astrometry of nearby bright stars is theoretically (in the photon noise limit) possible with a space corona graph using a wide field diffraction limited camera imaging an annulus of background stars around the central coronagraphic field. With the sub-micro arcsecond accuracy theoretically achievable on a 1.4-m telescope, the mass of all planets that can be imaged by the corona graph would be estimated. Simultaneous imaging and astrometric measurements would reduce the number of astrometric measurements necessary for mass determination, and reduce confusion between multiple planets and possible exozodiacal clouds in the coronagraphic image. While scientifically attractive, this measurement is technically very challenging, and must overcome astrometric distortions, which, in conventional telescopes, are several orders of magnitude above the photon noise limit. In this paper, we propose a new approach to calibrating astrometric distortions in the wide field imaging camera. The astrometric measurement is performed by simultaneously imaging background stars and diffraction spikes from the much brighter coronagraphic target on the same focal plane array. The diffraction spikes are generated by a series of small dark spots on the primary minor to reduce sensitivity to optical and mechanical distortions. Small scale distortions and detector errors are averaged down to sub-micro arcsecond by rolling the telescope around the line of sight. A preliminary error budget is shown and discussed to identify major sources of error for a 1.4-m telescope imaging a 0.25 squaredeg field of view at the galactic pole. © 2010 SPIE.
• Hattori, M., Colley, S., Garrel, V., Egner, S., Golota, T., Guyon, O., Ito, M., Minowa, Y., Oya, S., Saito, Y., Watanabe, M., Hayano, Y., Takami, H., & Iye, M. (2010). Recent development in real time control system of Subaru adaptive optics including laser guide star mode. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: We report recent development in real time control system of Subaru adaptive optics system. The main topic is modification of the real time control system for laser guide star operation. The primary change is appending lower order wave-front sensor. And also, an auxiliary tip-tilt and focus control are appended before higher order waver-front sensor to absorb the perturbation of the laser beam and height of sodium layer. Our implementations using the control gain matrix are introduced thoroughly from the basis of the system design and down to the details. Also, other new function and prospects in the near future will be presented for the cascaded average monitor and the time domain over sampling. © 2010 SPIE.
• Hayano, Y., Takami, H., Oya, S., Hattori, M., Saito, Y., Watanabe, M., Guyon, O., Minowa, Y., Egner, S. E., Ito, M., Garrel, V., Colley, S., Golota, T., & Iye, M. (2010). Commissioning status of Subaru laser guide star adaptive optics system. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: The current status of commissioning and recent results in performance of Subaru laser guide star adaptive optics system is presented. After the first light using natural guide stars with limited configuration of the system in October 2006, we concentrated to complete a final configuration for a natural guide star to serve A0188 to an open use observation. On sky test with full configurations using natural guide star started in August 2008, and opened to a public one month later. We continuously achieved around 0,6 to 0.7 of Strehl ratio at K band using a bright guide star around. 9th to 10th magnitude in R band. We found an unexpectedly large wavefront error in our laser launching telescope. The modification to fix this large wavefront error was made and we resumed the characterization of a laser guide star in February 2009. Finally we obtained a round-shaped laser guide star, whose image size is about 1.2 to 1.6 arcsec under the typical seeing condition. We are in the final phase of commissioning. A diffraction limited image by our AO system using a laser guide star will be obtained in the end of 2010. An open use observation with laser guide star system will start in the middle of 2011. ©2010 SPIE.
• Ito, M., Hayano, Y., Saito, Y., Takami, H., Iye, M., Hattori, M., Oya, S., Watanabe, M., Akagawa, K., Colley, S. A., Gorota, T. I., & Guyon, O. (2010). The characteristics of laser-transmission and guide star's brightness for Subaru LGS/AO188 system. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: We are commissioning the Laser Guide Star Adaptive Optics (LGS/A0188) system for Subaru Telescope at Hawaii, Mauna Kea. This system utilizes a combination of an all-solid-state mode-locked sum-frequency generation (SFG) laser (1.7GHz-bandwidth, 0.7ns-pulse width) as a light source and single-mode optical fiber for beam transference. However, optical fibers induce nonlinear scattering effects, such as stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS), beyond certain threshold levels in high-power lasers. We measured the laser transmission characteristics of a photonic crystal fiber (PCF) whose mode field diameter (MFD) was 11 μ m, and a step index fiber (SIF) cable whose MFD was 4.2 μ m to evaluate the threshold levels for non-linear effects. We observed SRS in the 200-m-long SIF when we input 1.3W. The material losses of them were 10db/km and 6.4dB/km, respectively. However, SRS and SBS were not induced in the 200-m-long PCF, even for an input power of 5.3W. As a result, we estimated the threshold of SRS to be 33W for the 35-m-long PCF designed for the Subaru LGSAO system. Other than SRS and SBS, we found self phase modulation (SPM) in our PCF. SPM makes the spectrum of the laser beam broaden and it causes less efficiency of generating bright LGS. We measured width of the spectrum by spectrum analyzer. As the result, we found it was 9.1GHz of full width half maximum (FWHM) in comparison with the original FWHM of our laser spectrum, 2.1GHz. This shows 70% of the laser energy for brightening the LGS was lost. We also measured the brightness of the LGS and evaluated its relationship with wavelength of the laser. The LGS' s brightness showed a peculiar tendency that did not be extinguish even though the wavelength has varied about 2pm. The tendency was not shown with the experiment using sodium gas cell. Therefore, it may be concerned the environment of the sodium layer in the mesosphere. © 2010 SPIE.
• Mateen, M., Garrel, V., Hart, M., & Guyon, O. (2010). Results from the laboratory demonstration of the non-linear curvature wavefront sensor. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: In this paper we show why a non-linear curvature wavefront sensor (nlCWFS) is superior to both Shack-Hartmann wavefront sensor (SHWFS) and conventional curvature wavefront sensor (cCWFS) for sensing mv < 15 natural guide stars. We have developed, an experimental setup aimed at comparing the the rms wavefront error obtained, with the nlCWFS and the SHWFS. We describe our experimental setup and present results from the laboratory demonstration of the nlCWFS. The non-linear approach, builds on the successful curvature wavefront sensing concept. The wavefront is reconstructed from the defocused pupil images using the Gerchberg-Saxton (GS) phase diversity algorithm. We compare results obtained from reconstructing the wavefront using a Shack-Hartmann wavefront sensor (SHWFS) and a nlCWFS for a monochromatic source. We discuss approaches to overcome non-linearity issues and discuss the challenge of using two WFSs in the same spatiotemporal control regime and the implementation of the nlCWFS on the 6.5 m MMT. © 2010 SPIE.
• Minowa, Y., Hayano, Y., Oya, S., Watanabe, M., Hattori, M., Guyon, O., Egner, S., Saito, Y., Ito, M., Takami, H., Garrel, V., Colley, S., Golota, T., & Iye, M. (2010). Performance of Subaru adaptive optics system AO188. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: Subaru adaptive optics system (AO188) is an 188-elements curvature sensor adaptive optics system that is operated in both natural and laser guide star modes. AO188 was installed at Nasmyth platform of the Subaru telescope and it has been successfully operating in the natural guide star mode since October 2008. The performance of AO188 in the natural guide star mode has been well verified from on-sky data obtained with the infrared camera and spectrograph (IRCS). Under normal seeing condition, AO188 achieves K-band Strehl ratio between 60% and 70% using R = 9.0 magnitude natural guide stars and it works well with faint guide stars down to R = 16.5 magnitude. We measured the FWHM and Strehl ratio of stellar images in globular clusters and found that the isoplanatic angle is approximately 30 arcsec. In this paper, we describe an overview of the operation procedure for AO188, as well as its performance such as angular resolution, Střehl ration, and sensitivity gain for detecting faint objects. © 2010 SPIE.
• Mueller, U., Stone, J., Peters, B. G., Daniel, J., Greene, T. P., Belikov, R., & Guyon, O. (2010). Narrow ion-beam figuring: A new tool to address extreme slopes on small surfaces located near telescope pupils. Proceedings of SPIE - The International Society for Optical Engineering, 7739.
  More info

  Abstract: Advanced shapes can now be produced for the corrective optics placed near a reimaged pupil, or even a deformable mirror surface. These surfaces can be improved and even apodization added to improve contrast. In this paper, we describe a special form of Narrow Ion Beam Figuring (NIBF) developed at L-3 Tinsley. In contrast to existing Ion Beam Figuring (IBF) machining schemes, the FWHM beam width is controlled in a much narrower band while still providing high beam currents. © 2010 SPIE.
• Murakami, N., Guyon, O., Martinache, F., Matsuo, T., Yokochi, K., Nishikawa, J., Tamura, M., Kurokawa, T., Baba, N., Vogt, F., Garrel, V., & Yoshikawa, T. (2010). An eight-octant phase-mask coronagraph for the Subaru coronagraphic extreme AO (SCExAO) system: System design and expected performance. Proceedings of SPIE - The International Society for Optical Engineering, 7735(PART 1).
  More info

  Abstract: An eight-octant phase-mask (EOPM) coronagraph is one of the highest performance coronagraphic concepts, and attains simultaneously high throughput, small inner working angle, and large discovery space. However, its application to ground-based telescopes such as the Subaru Telescope is challenging due to pupil geometry (thick spider vanes and large central obstruction) and residual tip-tilt errors. We show that the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system, scheduled to be installed onto the Subaru Telescope, includes key technologies which can solve these problems. SCExAO uses a spider removal plate which translates four parts of the pupil with tilted plane parallel plates. The pupil central obstruction can be removed by a pupil remapping system similar to the PIAA optics already in the SCExAO system, which could be redesigned with no amplitude apodization. The EOPM is inserted in the focal plane to divide a stellar image into eight-octant regions, and introduces a π-phase difference between adjacent octants. This causes a self-destructive interference inside the pupil area on a following reimaged pupil plane. By using a reflective mask instead of a conventional opaque Lyot stop, the stellar light diffracted outside the pupil can be used for a coronagraphic low-order wave-front sensor to accurately measure and correct tip-tilt errors. A modified inverse-PIAA system, located behind the reimaged pupil plane, is used to remove off-axis aberrations and deliver a wide field of view. We show that this EOPM coronagraph architecture enables high contrast imaging at small working angle on the Subaru Telescope. Our approach could be generalized to other phase-mask type coronagraphs and other ground-based telescopes. © 2010 Copyright SPIE - The International Society for Optical Engineering.
• Narita, N., Kudo, T., Bergfors, C., Nagasawa, M., Thalmann, C., Sato, B., Suzuki, R., Kandori, R., Janson, M., Goto, M., Brandner, W., Ida, S., Abe, L., Carson, J., Egner, S. E., Feldt, M., Golota, T., Guyon, O., Hashimoto, J., , Hayano, Y., et al. (2010). Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7. \pasj, 62, 779.
• Narita, N., Kudo, T., Bergfors, C., Nagasawa, M., Thalmann, C., Sato, B., Suzuki, R., Kandori, R., Janson, M., Goto, M., Brandner, W., Ida, S., Abe, L., Carson, J., Egner, S. E., Feldt, M., Golota, T., Guyon, O., Hashimoto, J., , Hayano, Y., et al. (2010). Search for outer massive bodies around transiting planetary systems: Candidates of faint stellar companions around HAT-P-7. Publications of the Astronomical Society of Japan, 62(3), 779-786.
  More info

  Abstract: We present results of direct imaging observations for HAT-P-7 taken with the Subaru HiCIAO and the Calar Alto AstraLux. Since the close-in transiting planet HAT-P-7b was reported to have a highly tilted orbit, massive bodies such as giant planets, brown dwarfs, and a binary star are expected to exist in the outer region of this system. We show that there are indeed two candidates for distant faint stellar companions around HAT-P-7. We discuss how such companions can play a role on the orbital evolution of HAT-P-7b. We conclude that since there is a third body in the system, as reported by Winn et al. (2009, ApJ, 763, L99), Kozai migration is less likely, while planet-planet scattering is possible. © 2010. Astronomical Society of Japan.
• Olivier, G. (2010). High sensitivity wavefront sensing with a nonlinear curvature wavefront sensor. Publications of the Astronomical Society of the Pacific, 122(887), 49-62.
  More info

  Abstract: A new wavefront sensing approach, derived from the successful curvature wavefront sensing concept but using a nonlinear phase retrieval wavefront reconstruction scheme, is described. The nonlinear curvature wavefront sensor (nlCWFS) approaches the theoretical sensitivity limit imposed by fundamental physics by taking full advantage of wavefront spatial coherence in the pupil plane. Interference speckles formed by natural starlight encode wavefront aberrations with the sensitivity set by the telescope's diffraction limit λ/D rather than the seeing limit of more conventional linear wavefront sensors (WFSs). Closed-loop adaptive optics simulations show that with an nlCWFS, a 100 nm rms wavefront error can be reached on an 8 m telescope on an mv = 13 natural guide star. The nlCWFS technique is best suited for high precision adaptive optics on bright natural guide stars. It is therefore an attractive technique to consider for direct imaging of exoplanets and disks around nearby stars, where achieved performance is set by wavefront control accuracy and exquisite control of low-order aberrations is essential for high contrast coronagraphic imaging. Performance gains derived from simulations are shown, and approaches for high speed reconstruction algorithms are briefly discussed. © 2009. The Astronomical Society of the Pacific. All rights reserved.
• Olivier, G., Pluzhnik, E., Martinache, F., Totems, J., Tanaka, S., Matsuo, T., Blain, C., & Belikov, R. (2010). High-Contrast imaging and wavefront control with a PIAA coronagraph: Laboratory system validation. Publications of the Astronomical Society of the Pacific, 122(887), 71-84.
  More info

  Abstract: The Phase-Induced Amplitude Apodization (PIAA) coronagraph is a high-performance corona-graph concept able to work at small angular separation with little loss in throughput. We present results obtained with a laboratory PIAA system including active wavefront control. The system has a 94.3% throughput (excluding coating losses) and operates in air with monochromatic light. Our testbed achieved a 2.27×10-7 raw contrast between 1.65λ/D (inner working angle of the coronagraph configuration tested) and 4.4λ/.D (outer working angle). Through careful calibration, we were able to separate this residual light into a dynamic coherent component (turbulence, vibrations) at 4.5 × 10-8 contrast and a static incoherent component (ghosts and/or polarization mismatch) at 1.6 × 10-7 contrast. Pointing errors are controlled at the 10-3 λ/D level using a dedicated low-order wavefront sensor. While not sufficient for direct imaging of Earthlike planets from space, the 2.27 × 10-7 raw contrast achieved already exceeds requirements for a ground-based extreme adaptive optics system aimed at direct detection of more massive exoplanets. We show that over a 4 hr period, averaged wavefront errors have been controlled to the 3.5 × 10-9 contrast level. This result is particularly encouraging for ground-based extreme-AO systems relying on long-term stability and absence of static wavefront errors to recover planets much fainter than the fast boiling speckle halo. © 2009. The Astronomical Society of the Pacific. All rights reserved.
• Oya, S., Hattori, M., Minowa, Y., Negishi, S., Tomono, D., Terada, H., Pyo, T., Watanabe, M., Itoh, M., Saito, Y., Egner, S., Hayano, Y., Takami, H., Iye, M., Guyon, O., Garrel, V., Colley, S., & Golota, T. (2010). Tip/tilt offload of Subaru AO188 by telescope secondary mirror. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: A tip/tilt off-load function from AO188 deformable mirror mount to Subaru telescope infrared secondary mirror has been implemented and tested. The function is effective to reduce the influence of strong background pattern at thermal infrared wavelengths. We describe the function and report the test results in this paper. ©2010 SPIE'.
• Saito, Y., Hayano, Y., Ito, M., Minowa, Y., Egner, S., Oya, S., Watanabe, M., Hattori, M., Garrei, V., Akagawa, K., Guyon, O., Colley, S., Golota, T., Saito, N., Takazawa, A., Ito, M., Takami, H., Wada, S., & Iye, M. (2010). The performance of the laser guide star system for the Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: We are developing a laser guide star (LGS) system for the 188-elements Adaptive Optics system (A0188) of the Subaru telescope. In this paper we describe the results of the performance tests of the LGS system. The beam that excites sodium atoms at 90 km altitude of the LGS is generated by the following sequence. The source of the beam is a quasi-CW mode locked sum-frequency generating 589 nm laser. This laser beam propagates through a diagnostics system for measuring the wavelength and the beam quality. Then it couples into a solidcore photonic crystal fiber cable for transmitting the beam to a telescope for launching the beam (LLT: Laser Launching Telescope). The output beam from this fiber cable is collimated by the optics mounted on the LLT. This collimated beam is expanded by the LLT and launched into the sky. We executed several engineering observations of the LGS system from 2009 for confirming the performance of all the components in this sequence. We also report the quality of the LGS. © 2010 SPIE.
• Thalmann, C., Grady, C. A., Goto, M., Wisniewski, J. P., Janson, M., Henning, T., Fukagawa, M., Honda, M., Mulders, G. D., Min, M., Moro-Martín, A., McElwain, M. W., Hodapp, K. W., Carson, J., Abe, L., Brandner, W., Egner, S., Feldt, M., Fukue, T., , Golota, T., et al. (2010). Imaging of a transitional disk gap in reflected light: Indications of plane formation around the young solar analog lkca 15. Astrophysical Journal Letters, 718(2 PART 2), L87-L91.
  More info

  Abstract: We present H- and Ks-band imaging data resolving the gap in the transitional disk around LkCa 15, revealing the surrounding nebulosity. We detect sharp elliptical contours delimiting the nebulosity on the inside as well as the outside, consistent with the shape, size, ellipticity, and orientation of starlight reflected from the far-side disk wall, whereas the near-side wall is shielded from view by the disk's optically thick bulk. We note that forward scattering of starlight on the near-side disk surface could provide an alternate interpretation of the nebulosity. In either case, this discovery provides confirmation of the disk geometry that has been proposed to explain the spectral energy distributions of such systems, comprising an optically thick disk with an inner truncation radius of ∼46 AU enclosing a largely evacuated gap. Our data show an offset of the nebulosity contours along the major axis, likely corresponding to a physical pericenter offset of the disk gap. This reinforces the leading theory that dynamical clearing by at least one orbiting body is the cause of the gap. Based on evolutionary models, our high-contrast imagery imposes an upper limit of 21MJup on companions at separations outside of 0. ″1 and of 13MJup outside of 0. ′2. Thus, we find that a planetary system around LkCa 15 is the most likely explanation for the disk architecture. © 2010. The American Astronomical Society.
• Thalmann, C., Grady, C., Goto, M., Wisniewski, J., Janson, M., Henning, T., Fukagawa, M., Honda, M., Mulders, G., Min, M., Moro-Mart{\'\in}, A., McElwain, M., Hodapp, K., Carson, J., Abe, L., Brandner, W., Egner, S., Feldt, M., Fukue, T., , Golota, T., et al. (2010). Imaging of a Transitional Disk Gap in Reflected Light: Indications of Planet Formation Around the Young Solar Analog LkCa 15. \apjl, 718(2), L87-L91.
• Trauger, J., Stapelfeldt, K., Traub, W., Krist, J., Moody, D., Mawet, D., Serabyn, E., Henry, C., Brugarolas, P., Alexander, J., Gappinger, R., Dawson, O., Mireles, V., Park, P., Pueyo, L., Shaklan, S., Guyon, O., Kasdin, J., Vanderbei, R., , Spergel, D., et al. (2010). ACCESS - A Concept Study for the Direct Imaging and Spectroscopy of Exoplanetary Systems. Proceedings of SPIE - The International Society for Optical Engineering, 7731.
  More info

  Abstract: ACCESS is one of four medium-class mission concepts selected for study in 2008-9 by NASA's Astrophysics Strategic Mission Concepts Study program. ACCESS evaluates a space observatory designed for extreme high-contrast imaging and spectroscopy of exoplanetary systems. An actively-corrected coronagraph is used to suppress the glare of diffracted and scattered starlight to contrast levels required for exoplanet imaging. The ACCESS study considered the relative merits and readiness of four major coronagraph types, and modeled their performance with a NASA medium-class space telescope. The ACCESS study asks: What is the most capable medium-class coronagraphic mission that is possible with telescope, instrument, and spacecraft technologies available today? Using demonstrated high-TRL technologies, the ACCESS science program surveys the nearest 120+ AFGK stars for exoplanet systems, and surveys the majority of those for exozodiacal dust to the level of 1 zodi at 3 AU. Coronagraph technology developments in the coming year are expected to further enhance the science reach of the ACCESS mission concept. © 2010 SPIE.
• Vogt, F., Martinache, F., Guyon, O., Yoshikawa, T., Yokochi, K., Garrel, V., & Matsuo, T. (2010). The subaru coronographic extreme AO (SCExAO) system: Implementation and performances of the coronographic low order WaveFront sensor. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: The Subaru Coronagraphic Extreme AO project (SCExAO) is a high performance coronagraph designed to deliver high contrast at small angular separation. For the detection of structures near the diffraction limit, an accurate control of low order wavefront aberrations - tip-tilt and focus - is essential as these aberrations create light leaks that are the source of confusion in the final science image. To address this major difficulty, we have equipped SCExAO with a specially designed Coronagraphic Low Order WaveFront Sensor (CLOWFS) using defocused images of a reflective ring located in the focal plane, that can track tip-tilt errors as small as 10-3λ/D. CLOWFS was originally designed to drive actuators in a closed-loop. Here, we show that it can also be used in post-processing to efficiently subtract the tip-tilt induced coronagraphic leaks in the final science image. © 2010 SPIE.
• Watanabe, M., Ito, M., Oya, S., Hayano, Y., Minowa, Y., Hattori, M., Saito, Y., Egner, S., Takami, H., Iye, M., Guyon, O., Garrei, V., Colley, S., & Golota, T. (2010). Visible low-order wavefront sensor for the subaru LGSAO system. Proceedings of SPIE - The International Society for Optical Engineering, 7736(PART 1).
  More info

  Abstract: The Subaru laser guide star adaptive optics system (A0188) was installed at the Nasmyth focus of the Subaru Telescope on October 2006 and it is in operation with the natural guide star (NGS) mode. The operation of the laser guide star (LGS) mode started on January 2010. A visible low-order wavefront sensor (LOWFS) was built to measure tip-tilt and defocus terms of wavefront by using a single NGS within a 2.7 arcmin diameter field when an LGS is used for high-order wavefront sensing with the 188-element curvature based wavefront sensor. This LOWFS is a 2 x 2 sub-aperture Shack-Hartmann sensor with 16 photon-counting avalanche photodiode (APD) modules. A 4x4-element lenslet array is located after the 2x2 sub-aperture Shack-Hartmann lenslet array and it is coupled with the APD modules through optical fibers. The field of view of the LOWFS is 4 arcsec in diameter. It has own guide star acquisition unit, acquisition and pupil cameras, and atmospheric dispersion corrector. We describe the design, construction, and integration of this low-order wavefront sensor. © 2010 SPIE.
• Belikov, R., Pluzhnik, E., Connelley, M. S., Witteborn, F. C., Lynch, D. H., Cahoy, K. L., Guyon, O., Greene, T. P., & McKelvey, M. E. (2009). First results on a new PIAA coronagraph testbed at NASA Ames. Proceedings of SPIE - The International Society for Optical Engineering, 7440.
  More info

  Abstract: Direct imaging of extrasolar planets, and Earth-like planets in particular, is an exciting but difficult problem requiring a telescope imaging system with 1010 contrast at separations of 100mas and less. Furthermore, the current NASA science budget may only allow for a small 1-2m space telescope for this task, which puts strong demands on the performance of the imaging instrument. Fortunately, an efficient coronagraph called the Phase Induced Amplitude Apodization (PIAA) coronagraph has been maturing and may enable Earth-like planet imaging for such small telescopes. In this paper, we report on the latest results from a new testbed at NASA Ames focused on testing the PIAA coronagraph. This laboratory facility was built in 2008 and is designed to be flexible, operated in a highly stabilized air environment, and to complement existing efforts at NASA JPL. For our wavefront control we are focusing on using small Micro-Electro- Mechanical-System deformable mirrors (MEMS DMs), which promises to reduce the size of the beam and overall instrument, a consideration that becomes very important for small telescopes. At time of this writing, we are operating a refractive PIAA system and have achieved contrasts of about 1.2x10-7 in a dark zone from 2.0 to 4.8 λ/D (with 6.6x10 -8 in selected regions). In this paper, we present these results, describe our methods, present an analysis of current limiting factors, and solutions to overcome them. © 2009 Copyright SPIE - The International Society for Optical Engineering.
• Cahoy, K., Guyon, O., Schneider, G., Marley, M., Belikov, R., Meyer, M., Ridgway, S., Traub, W., & Woolf, N. (2009). Science performance of the Pupil-mapping Exoplanet Coronagraphic Observer (PECO). Proceedings of SPIE - The International Society for Optical Engineering, 7440.
  More info

  Abstract: The Pupil-mapping Exoplanet Coronagraphic Observer (PECO) medium-class mission concept is a 1.4-m space-based optical telescope with a high-performance Phase-Induced Amplitude Apodization (PIAA) coronagraph. PECO detects and characterizes exoplanets and their host systems at 2 λ/D (0.15") separation at high contrast (∼1e-10). The optical design images in 16 filter bands from 400-800 nm, producing simultaneous low-resolution target spectra. PECO will characterize terrestrial planets in the habitable zones of ∼20 nearby F, G, K stars at spectral resolution of R∼15, as well as over a dozen radial-velocity planets and over a hundred gas giants and exozodiacal dust disks. We discuss PECO's expected science performance and simulated data products over its three-year mission lifetime. © 2009 Copyright SPIE - The International Society for Optical Engineering.
• Greene, T., Cahoy, K., Guyon, O., Kasting, J., Marley, M., Meyer, M., Ridgway, S., Schneider, G., Traub, W., & Woolf, N. (2009). Discovering and Characterizing the Planetary Systems of Nearby Stars: The scientific need for medium aperture space coronagraph observations. arXiv e-prints, arXiv:0902.4219.
• Guyon, O., Matsuo, T., & Angel, R. (2009). Coronagraphic Low-Order Wave-Front Sensor: Principle and Application to a Phase-Induced Amplitude Coronagraph. \apj, 693(1), 75-84.
• Hayano, Y., Takami, H., Oya, S., Hattori, M., Saito, Y., Watanabe, M., Minowa, Y., Egner, S., Guyon, O., Ito, M., Garrel, V., Colley, S., Dinkins, M., Taras, G., Kurakami, T., Nabeshima, Y., Saito, N., Wada, S., Shibuya, T., & Iye, M. (2009). A laser guide star adaptive optics system of subaru telescope. Optics InfoBase Conference Papers.
  More info

  Abstract: A curvature-wavefront-based AO system for operation with a laser guide star is in commissioning phase at Subaru Telescope. The AO system has been offered for astronomers since September 2008 using a natural guide star. This paper introduces briefly the laser system for generating a laser guide star and reports the characteristics of laser guide star on sky. The total equivalent magnitude of the laser guide star is estimated to be 10.7 magnitude. The angular size of laser guide star is around 2 arc second FWHM under a seeing condition of 1 arc second in K-band. © 2008 Optical Society of America.
• Kern, B., Belikov, R., Give'on, A., Guyon, O., Kuhnert, A., Levine-West, M. B., McMichael, I. C., Moody, D. C., Niessner, A. F., Pueyo, L., Shaklan, S. B., Traub, W. A., & Trauger, J. T. (2009). Phase-Induced Amplitude Apodization (PIAA) coronagraph testing at the high contrast imaging testbed. Proceedings of SPIE - The International Society for Optical Engineering, 7440.
  More info

  Abstract: We present the current status of our testing of a phase-induced amplitude apodization (PIAA) coronagraph at the Jet Propulsion Lab's High Contrast Imaging Testbed (HCIT) vacuum facilities. These PIAA optics were designed to produce a point-spread function containing a region whose intensity is below 10 -9 over a 20-percent fractional bandpass, comparable to the requirements for direct imaging of exoplanets from space. The results presented here show contrast levels of 4×10-7 in monochromatic light, with an inner working angle of 2.4 λ/D. The instrumentation is described here, as well as the testing procedures, wavefront control, and results. © 2009 Copyright SPIE - The International Society for Optical Engineering.
• Krist, J. E., Moody, D. C., Mawet, D., Trauger, J. T., Belikov, R., Shaklan, S. B., Guyon, O., & Vanderbei, R. J. (2009). End-to-end simulations of different coronagraphic techniques. Proceedings of SPIE - The International Society for Optical Engineering, 7440.
  More info

  Abstract: The NASA exoplanet exploration program is dedicated to developing technologies for detecting and characterizing extrasolar planets. In support of that program we have evaluated three different coronagraphic techniques (bandlimited Lyot, optical vortex, and phase-induced pupil apodization) using optical propagation simulations. These utilized a complete hypothetical telescope+coronagraph system with phase and amplitude aberrations. Wavefront control using dual sequential deformable mirrors was performed. We discuss the different computational techniques necessary to accurately simulate each coronagraph. © 2009 Copyright SPIE - The International Society for Optical Engineering.
• Levine, M., Lisman, D., Shaklan, S., Kasting, J., Traub, W., Alexander, J., Angel, R., Blaurock, C., Brown, M., Brown, R., Burrows, C., Clampin, M., Cohen, E., Content, D., Dewell, L., Dumont, P., Egerman, R., Ferguson, H., Ford, V., , Greene, J., et al. (2009). Terrestrial Planet Finder Coronagraph (TPF-C) Flight Baseline Concept. arXiv e-prints, arXiv:0911.3200.
• Lozi, J., Martinache, F., & Guyon, O. (2009). Phase-Induced Amplitude Apodization on Centrally Obscured Pupils: Design and First Laboratory Demonstration for the Subaru Telescope Pupil. \pasp, 121(885), 1232.
• Lozi, J., Martinache, F., & Guyon, O. (2009). Phase-induced amplitude apodization on centrally obscured pupils: Design and first laboratory demonstration for the subaru telescope pupil. Publications of the Astronomical Society of the Pacific, 121(885), 1232-1244.
  More info

  Abstract: High-contrast coronagraphic imaging is challenging for telescopes with central obstructions and thick spider vanes, such as the Subaru Telescope. We present in this article the first laboratory demonstration of a high-efficiency PIAA-type coronagraph on such a pupil, using coronagraphic optics which will be part of the Subaru Coronagraphic Extreme-AO (SCExAO) system currently under assembly. Lossless pupil apodization is performed by a set of aspheric PIAA lenses specifically designed to also remove the pupil's central obstruction, coupled with a spider removal plate (SRP) which removes spider vanes by translating four parts of the pupil with tilted planeparallel plates. An "inverse-PIAA" system, located after the coronagraphic focal plane mask, is used to remove off-axis aberrations and deliver a wide field of view. Our results validate the concept adopted for the SCExAO system, and show that the Subaru Telescope pupil can be properly apodized for high-contrast coronagraphic imaging as close as≈1 λ/D with no loss of sensitivity. We also verify that off-axis aberrations in the system are in agreement with theory, and that the inverse PIAA system recovers a wide usable field of view for exoplanet detection and disks imaging. © 2009. The Astronomical Society of the Pacific. All rights reserved.
• Martinache, F., & Guyon, O. (2009). The Subaru coronagraphic extreme-AO project. Proceedings of SPIE - The International Society for Optical Engineering, 7440.
  More info

  Abstract: The Subaru Coronagraphic Extreme AO (SCExAO) Project is an upgrade to the newly commissioned coronagraphic imager HiCIAO for the Subaru Telescope, in the context of a massive survey for exoplanets and disks called SEEDS. SCExAO combines a high-performance coronagraph PIAA coronagraph and non-redundant aperture masking interferometry to a MEMS-based wavefront control system to be used in addition to the 188- actuator Subaru Adaptive Optics (AO188) system. The upgrade is designed as a flexible platform with easy access to both pupil and image planes to allow quick implementation of new high-angular resolution techniques, using a combination of interferometry and coronagraphy. The SCExAO system will enhance SEEDS by offering access to smaller separations and improved PSF calibration, and will therefore allow high quality follow-up observations of challenging SEEDS candidates. SCExAO will also enable new science investigations requiring high contrast imaging of the innermost (< 0.2 arc second) surrounding of stars. © 2009 Copyright SPIE - The International Society for Optical Engineering.
• Blain, C., Guyon, O., Conan, R., & Bradley, C. (2008). Simple iterative method for open-loop control of MEMS deformable mirrors. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: The Adaptive Optics Laboratory at the University of Victoria (Canada) and the Subaru Telescope NAOJ (Hawaii) are collaborating to develop a simple method allowing open-loop control of MEMS deformable mirrors. This method consists of an iterative algorithm based on 3 simple equations and 4 constants. The 4 constants are different for each mirror, therefore a characterization step is necessary to evaluate their values for a given mirror. In this paper we describe the model and the 3 equations it relies on. We also propose a characterization methodology and finally present the preliminary results respectively obtained on Victoria and Subaru test beds.
• Enya, K., Abe, L., Haze, K., Tanaka, S., Nakagawa, T., Kataza, H., Higuchi, S., Miyata, T., Sako, S., Nakamura, T., Tamura, M., Nishikawa, J., Murakami, N., Itoh, Y., Wakayama, T., Sato, T., Nakagiri, N., Guyon, O., Venet, M., & Bierden, P. (2008). Mid-infrared coronagraph for SPICA. Proceedings of SPIE - The International Society for Optical Engineering, 7010.
  More info

  Abstract: The SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is a infrared space-borne telescope mission of the next generation following AKARI. SPICA will carry a telescope with a 3.5 m diameter monolithic primary mirror and the whole telescope will be cooled to 5 K. SPICA is planned to be launched in 2017, into the sun-earth L2 libration halo orbit by an H II-A rocket and execute infrared observations at wavelengths mainly between 5 and 200 micron. The large telescope aperture, the simple pupil shape, the capability of infrared observations from space, and the early launch gives us with the SPICA mission a unique opportunity for coronagraphic observation. We have started development of a coronagraphic instrument for SPICA. The primary target of the SPICA coronagraph is direct observation of extra-solar Jovian planets. The main wavelengths of observation, the required contrast and the inner working angle (IWA) of the SPICA coronagraph are set to be 5-27 micron (3.5-5 micron is optional), 10-6, and a few λ/D (and as small as possible), respectively, in which λ is the observation wavelength and D is the diameter of the telescope aperture (3.5m). For our laboratory demonstration, we focused first on a coronagraph with a binary shaped pupil mask as the primary candidate for SPICA because of its feasibility. In an experiment with a binary shaped pupil coronagraph with a He-Ne laser (λ=632.8nm), the achieved raw contrast was 6.7×10-8, derived from the average measured in the dark region without active wavefront control. On the other hand, a study of Phase Induced Amplitude Apodization (PIAA) was initiated in an attempt to achieve better performance, i.e., smaller IWA and higher throughput. A laboratory experiment was performed using a He-Ne laser with active wavefront control, and a raw contrast of 6.5×10-7 was achieved. We also present recent progress made in the cryogenic active optics for SPICA. Prototypes of cryogenic deformable by Micro Electro Mechanical Systems (MEMS) techniques were developed and a first demonstration of the deformation of their surfaces was performed with liquid nitrogen cooling. Experiments with piezo-actuators for a cryogenic tip-tilt mirror are also ongoing.
• Guyon, O. (2008). Ultra-high sensitivity wavefront sensing for extreme-AO. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: A new wavefront sensing scheme derived from curvature wavefront sensing is presented. Non-linear Curvature wavefront sensing (NLCWFS) is a scheme derived from conventional curvature wavefront sensing. NLCWFS uses four defocused pupil images and a non-linear wavefront reconstruction. NLCWFS is largely achromatic and does not require a flat (
• Guyon, O., Blain, C., Takami, H., Hayano, Y., Hattori, M., & Watanabe, M. (2008). Improving the Sensitivity of Astronomical Curvature Wavefront Sensor Using Dual-Stroke Curvature. \pasp, 120(868), 655.
• Guyon, O., Blain, C., Takami, H., Hayano, Y., Hattori, M., & Watanabe, M. (2008). Improving the sensitivity of astronomical curvature wavefront sensor using dual-stroke curvature. Publications of the Astronomical Society of the Pacific, 120(868), 655-664.
  More info

  Abstract: Curvature wavefront sensors measure wavefront phase aberration by acquiring two intensity images on either side of the pupil plane. Low-order adaptive optics (AO) systems using curvature wavefront sensing (CWFS) have proved to be highly efficient for astronomical applications: they are more sensitive, use fewer detector elements, and achieve, for the same number of actuators, higher Strehl ratios than AO systems using more traditional Shack-Hartmann wavefront sensors. In higher-order systems, however, curvature wavefront sensors lose sensitivity to low spatial frequencies wavefront aberrations. This effect, often described as "noise propagation," limits the usefulness of curvature wavefront sensing for high-order AO systems and/or large telescopes. In this paper, we first explain how this noise propagation effect occurs and then show that this limitation can be overcome by acquiring four defocused images of the pupil instead of two. This solution can be implemented without significant technology development and can run with a simple linear wavefront reconstruction algorithm at > kHz speed. We have successfully demonstrated in the laboratory that the four conjugation planes can be sequentially obtained at > kHz speed using a speaker-vibrating membrane assembly commonly used in current curvature AO systems. Closed loop simulations show that implementing this scheme is equivalent to making the guide star 1 to 1.5 magnitude brighter for the configuration tested (188 actuator elements on 8-m telescope). Higher sensitivity gains are expected on curvature systems with higher number of actuators. © 2008. The Astronomical Society of the Pacific. All rights reserved.
• Hayano, Y., Takami, H., Guyon, O., Oya, S., Hattori, M., Saito, Y., Watanabe, M., Murakami, N., Minowa, Y., Ito, M., Colley, S., Eldred, M., Golota, T., Dinkins, M., Kashikawa, N., & Lye, M. (2008). Current status of the laser guide star adaptive optic system for Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: The current status and recent results' since last SPIE conference at Orlando in 2006' for the laser guide star adaptive optics system for Subaru Telescope is presented. We had a first light using natural guide star and succeed to launch the sodium laser beam in October 2006. The achieved Strehl ratio on the 10th magnitude star was around 0.5 at K band. We confirmed that the full-width-half-maximum of the stellar point spread function is smaller than 0.1 arcsec even at the 0.9 micrometer wavelehgth. The size of the artificial guide star by the laser beam tuned at the wavelength of 589 nm was estimated to be 10 arcsec. The obtained blurred artificial guide star is caused by the wavefront error on the laser launching telescope. After the first light and first launch' we found that we need to modify and to fix the components' which are temporarily finished. Also components' which were postponed to fabricate after the first light' are required to build newly. All components used by the natural guide star adaptive optics system are finalized recently and we are ready to go on the sky. Next engineering observation is scheduled in August' 2008.
• Hodapp, K. W., Suzuki, R., Tamura, M., Abe, L., Suto, H., Kandori, R., Morino, J., Nishimura, T., Takami, H., Guyon, O., Jacobson, S., Stahlberger, V., Yamada, H., Shelton, R., Hashimoto, J., Tavrov, A., Nishikawa, J., Ukita, N., Izumiura, H., , Hayashi, M., et al. (2008). HiCIAO: The subaru telescope's new high-contrast coronographic imager for adaptive optics. Proceedings of SPIE - The International Society for Optical Engineering, 7014.
  More info

  Abstract: The High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO), is a coronographic simultaneous differential imager for the new 188-actuator AO system at the Subaru Telescope Nasmyth focus. It is designed primarily to search for faint companions, brown dwarves and young giant planets around nearby stars, but will also allow observations of disks around young stars and of emission line regions near other bright central sources. HiCIAO will work in conjunction with the new Subaru Telescope 188-actuator adaptive optics system. It is designed as a flexible,experimental instrument that will grow from the initial, simple coronographic system into more complex, innovative optics as these technologies become available. The main component of HiCIAO is an infrared camera optimized for spectral simultaneous differential imaging that uses a Teledyne 2.5 ?m HAWAII-2RG detector array operated by a Sidecar ASIC. This paper reports on the assembly, testing, and "first light" observations at the Subaru Telescope.
• Minowa, Y., Takami, H., Watanabe, M., Hayano, Y., Miyake, M., Iye, M., Oya, S., Hattori, M., Murakami, N., Guyon, O., Saito, Y., Itoh, M., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2008). Development of a dichroic beam splitter for Subaru AO188. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: We have developed a dichroic beam splitter for the Subaru AO188, which reflects optical light (0.4-0.9 μm) for wavefront sensing and transmits near-infrared light (0.93-5.2 μm) for science observations. The beam splitter is made of 145mm × 200mm calcium fluoride substrate coated by fluoride and metal chalcogen compound multilayer, which should be a best way to realize high transmittance over wide wavelength range in the near infrared. However, since typical fluoride soft coating is less resistant to the moisture in the air, the fluoride coating become damaged as we use on the AO188 optical bench which is placed in the room temperature condition. We have performed several accelerated endurance tests of the beam splitter under high-humidity condition by changing the design of the coatings, and found an optimal solution with an oxide protection layer which prevents the damage of the dichroic coating and keeps high transmittance at near-infrared wavelength. In this paper, we report the results of the endurance tests and the performance of our dichroic beam splitter.
• Oya, S., Minowa, Y., Hattori, M., Watanabe, M., Hayano, Y., Itoha, M., Saito, Y., Takami, H., Iye, M., Guyon, O., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2008). Characterization of vibrating shape of a bimorph deformable mirror. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: Actual measurement of vibrating shape of a bimorph deformable mirror is presented to discuss the characteristics of resonance. Understanding the vibration properties of a bimorph deformable mirror is a key issue to overcome resonance problem, a major drawback of this type of deformable mirror, and to make full use of its advantages. Two-dimensional vibrating shape of the deformable mirror surface, not only at a point, is essential to figure out the resonance behavior. The results are informative for improvement of mechanical design or control software.
• Schneider, J., Boccaletti, A., Aylward, A., Baudoz, P., Beuzit, J. -., Brown, R., Cho, J., Dohlen, K., Ferrari, M., Galicher, R., Grasset, O., Grenfell, L., Griessmeier, J. -., Guyon, O., Hough, J., Kasper, M., Keller, C., Longmore, A., Lopez, B., , Martin, E., et al. (2008). Diversity among other worlds: characterization of exoplanets by direct detection. arXiv e-prints, arXiv:0811.2496.
• Shao, M., Bairstow, S., Levine, B. M., Vasisht, G., Lane, B. F., Vasudevan, G., Woodruff, R., Samuele, R., Wynn, J., Clampin, M., Lyon, R., & Guyon, O. (2008). DAVINCI, a diluter aperture visible nulling coronagraphic instrument. Proceedings of SPIE - The International Society for Optical Engineering, 7013.
  More info

  Abstract: DAVINCI is a dilute aperture nulling coronagraph that has the potential of directly detecting an Earth in the habitable zone around ∼100 nearby stars. The novel feature of this mission concept is to replace a filled aperture 5-6 meter telescope with 4 by 1.1 meter telescopes in a phased array, dramatically reducing the cost by potentially by a factor of 5-10.
• Trauger, J., Stapelfeldt, K., Traub, W., Henry, C., Krist, J., Mawet, D., Moody, D., Park, P., Pueyo, L., Serabyn, E., Shaklan, S., Guyon, O., Kasdin, J., Spergel, D., Vanderbei, R., Belikov, R., Marcy, G., Brown, R. A., Schneider, J., , Woodgate, B., et al. (2008). ACCESS - A NASA mission concept study of an actively-corrected coronagraph for exoplanet system studies. Proceedings of SPIE - The International Society for Optical Engineering, 7010.
  More info

  Abstract: ACCESS (Actively-Corrected Coronagraph for Exoplanet System Studies) develops the science and engineering case for an investigation of exosolar giant planets, super-earths, exo-earths, and dust/debris fields that would be accessible to a medium-scale NASA mission. The study begins with the observation that coronagraph architectures of all types (other than the external occulter) call for an exceptionally stable telescope and spacecraft, as well as active wavefront correction with one or more deformable mirrors (DMs). During the study, the Lyot, shaped pupil, PIAA, and a number of other coronagraph architectures will all be evaluated on a level playing field that considers science capability (including contrast at the inner working angle (IWA), throughput efficiency, and spectral bandwidth), engineering readiness (including maturity of technology, instrument complexity, and sensitivity to wavefront errors), and mission cost so that a preferred coronagraph architecture can be selected and developed for a medium-class mission.
• Watanabe, M., Oya, S., Hayano, Y., Takami, H., Hattori, M., Minowa, Y., Saito, Y., Ito, M., Murakami, N., Iye, M., Guyon, O., Colley, S., Eldred, M., Golota, T., & Dinkins, M. (2008). Implementation of 188-element curvature-based wavefront sensor and calibration source unit for the subaru LGSAO system. Proceedings of SPIE - The International Society for Optical Engineering, 7015.
  More info

  Abstract: The Subaru laser guide star adaptive optics (AO) system was installed at the Nasmyth focus of the Subaru Telescope, and had the first light with natural guide star on October 2006. The AO system has a 188-element curvature based wavefront sensor with photon-counting avalanche photodiode (APD) modules. It measures highorder terms of wavefront using either of a single laser (LGS) or natural guide star (NGS) within a 2' diameter field. The AO system has also a source simulator. It simulates LGS and NGS beams, simultaneously, with and without atmospheric turbulence by two turbulent layer at about 0 and 6 km altitudes, and reproduces the cone effect for the LGS beam. We describe the design, construction, and integration of the curvature wavefront sensor and calibration source unit.
• Abe, L., Enya, K., Tanaka, S., Nakagawa, T., Kataza, H., Tamura, M., & Guyon, O. (2007). Detecting extra-solar planets with the Japanese 3.5 m SPICA space telescope. Comptes Rendus Physique, 8(3-4), 374-384.
  More info

  Abstract: We present the 3.5 m SPace Infrared telescope for Cosmology and Astrophysics (SPICA) space telescope, the launch of which is schedule around year 2015 by the Japanese HII-A rocket, and specifically discuss its use in the context of direct observation of extra-solar planets. This actively cooled (4.5 K), single aperture telescope will operate in the mid and far infrared spectral regions, and up to submillimetric wavelengths (200 μm). The lowest spectral region (5 to 20 μm), where the spatial resolution is the most favorable, will be dedicated to high contrast imaging with coronagraphy. This article describes the SPICA coronagraph project in terms of science, as well as our efforts to study a suitable instrumental concept, compatible with the constraints of the telescope architecture. To cite this article: L. Abe et al., C. R. Physique 8 (2007). © 2007 Académie des sciences.
• Enyat, K., Abe, L., Tanaka, S., Haze, K., Venet, M., Nakagawa, T., Kataza, H., Tamura, M., Nishikawa, J., Murakami, N., Fujita, K., Itoh, Y., Guyon, O., Pluzhnik, E. A., Wakayama, T., Sato, T., & Nakagiri, N. (2007). Coronagraph project with the SPICA mission. Proceedings of SPIE - The International Society for Optical Engineering, 6693.
  More info

  Abstract: We present the status of the development of a coronagraph for the Space Infrared telescope for Cosmology and Astrophysics (SPICA). SPICA is the next generation of infrared space-borne telescope missions following to AKARI, led by Japan. SPICA will carry a telescope that has a 3.5 m diameter monolithic primary mirror and the whole telescope will be cooled to 4.5 K. It is planned to launch SPICA into the sun-earth L2 libration halo orbit using H II-A rocket in the middle of the 2010s and execute infrared observations at wavelengths mainly between 5 and 200 micron. The SPICA mission gives us a unique opportunity for coronagraph observations, because of the large telescope aperture, the simple pupil shape, the capability of infrared observations from space, and the early launch. We have started development of the SPICA coronagraph in which the primary target is direct observation of extra-solar Jovian planets. The main wavelengths of observation, the required contrast and the inner working angle (IWA) of the SPICA coronagraph instrument are set to be 5-27 micron, 10 -6, and a few λ/D (and as small as possible), respectively, in which λ is the observation wavelength and D is the diameter of the telescope aperture (3.5m). We focused on a coronagraph with a binary shaped pupil mask as the primary candidate for SPICA because of its feasibility. Nano-fabrication technology using electron beam lithography was applied to manufacture a high precision mask and a laboratory experiment with a He-Ne laser (λ=632.8nm) was performed in air without active wavefront control. The raw contrast derived from the average measured in the dark region reached 6.7×10-8. On the other hand, a study of Phase Induced Amplitude Apodization (PIAA) was started in an attempt to achieve higher performance, i.e., smaller IWA and higher throughput. A hybrid solution using PIAA and a shaped pupil mask was proposed. A laboratory experiment was performed using a He-Ne laser with active wavefront control via a 32 × 32 channel deformable mirror. A raw contrast of 6.5 × 10-7 was achieved. Designs of binary shaped pupil mask are presented for the actual SPICA pupil which is obstructed by the telescope's secondary mirror and its support. Subtraction of point spread function (PSF) was also evaluated.
• Guyon, O. (2007). A theoretical look at coronagraph design and performance for direct imaging of exoplanets. Comptes Rendus Physique, 8(3-4), 323-332.
  More info

  Abstract: New coronagraph concepts are being proposed at an increasing rate. In this article, I look at the intrinsic performance each concept can theoretically offer for direct detection of exoplanets. Fundamental physics sets quantifiable limits on the performance of coronagraphs. This theoretical work provides valuable insight into how to design high performance coronagraphs, explains many of the characteristics of particular designs and reveals the importance of stellar angular diameter on coronagraph performance. This study shows that the PIAA coronagraph appears to be extremely attractive for direct imaging of exoplanets. Recent results obtained in the laboratory with this coronagraph are briefly presented. To cite this article: O. Guyon, C. R. Physique 8 (2007). © 2007 Académie des sciences.
• Guyon, O. (2007). High performance curvature wavefront sensing for extreme-AO. Proceedings of SPIE - The International Society for Optical Engineering, 6691.
  More info

  Abstract: Despite promising results,1,2 Curvature wavefront sensing is usually not considered as an option for future AO systems such as AO systems for Extremely Large Telescopes (ELTs) or high order systems for the current generation of 8 to 10m telescopes. CWFS is generally thought to be useful only for low order systems, both for technical reasons (detector and DM technology) and fundamental reasons (noise propagation for high order curvature systems). I show in this paper that these worries are unjustified, and that, thanks to newly developed techniques and algorithms, CWFS is in fact much superior to more traditional Shack-Hartman wavefront sensing: (1) CWFS can be made extremely efficient, even for a high order system, thanks to a new "multi- stroke" curvature wavefront sensing mode (2) CWFS-based systems can efficiently utilize both piezo-stack type deformable mirrors and square pixel detector array, and there is therefore no reason to think that technological considerations limit CWFS-based systems to low-order correction (3) non-linear Fourier-based CWFS control algorithms can dramatically increase the performance of existing and future CWFS-based systems.
• Shaklan, S. B., Give'on, A., Belikov, R., Pueyo, L., & Guyon, O. (2007). Broadband wavefront control in a pupil mapping coronagraph. Proceedings of SPIE - The International Society for Optical Engineering, 6693.
  More info

  Abstract: Pupil mapping (a.k.a. Phase-Induced Amplitude Apodization, or PIAA) is a promising technique in high-dynamic range stellar coronagraphy that obtains higher throughput and better inner working angle than any other known approach. As with any coronagraph, the optical surface requirements and the diameter of the controllable region in the image plane are tied to the wavefront control system and optical bandpass. For example, in a monochromatic bandpass, a single ideal deformable mirror (DM) can create a dark hole with a diameter limited by its Nyquist frequency, even for highly aberrated optics. In broadband light, the depth of the dark hole is linked to the wavelength dependence of aberrations, their spatial frequency content, and their propagation through the system. We derive requirements on the surface height and reflectivity power spectral densities for optics in the PIAA system and describe a sequential-DM architecture that will achieve high-contrast over a large optical bandwidth.
• Stapelfeldt, K., Trauger, J., Traub, W., Clampin, M., Oegerle, W., Wiseman, J., & Guyon, O. (2007). First Steps in Direct Imaging of Planetary Systems Like our Own: The Science Potential of 2-m Class Optical Space Telescopes. arXiv e-prints, arXiv:0707.1886.
• Guyon, O., & Shao, M. (2006). The Pupil-swapping Coronagraph. \pasp, 118(844), 860-865.
• Guyon, O., & Shao, M. (2006). The pupil-swapping coronagraph. Publications of the Astronomical Society of the Pacific, 118(844), 860-865.
  More info

  Abstract: A new coronagraph that performs destructive interference between copies of the telescope pupil in which "slices" have been swapped is studied in this paper. A fourth-order "pupil-swapping coronagraph" is particularly attractive for direct imaging of extrasolar terrestrial planets: it achieves 100% throughput at 1.4λ/d on a square pupil (72,5% at 1.77λ/d on a circular pupil), is compatible with a central obstruction and spiders, and delivers sharp images of off-axis sources. Direct detection of extrasolar terrestrial planets appears theoretically feasible on a 2 to 3 m visible-wavelength telescope in space. © 2006. The Astronomical Society of the Pacific. All rights reserved.
• Guyon, O., Gallet, B., Pluzhnik, E. A., Takami, H., & Tamura, M. (2006). High contrast imaging with focal plane wavefront sensing for ground based telescopes. Proceedings of SPIE - The International Society for Optical Engineering, 6272 II.
  More info

  Abstract: The techniques adopted in "classical" AO (sensing in the visible, imaging in the near-IR) limit the achievable raw PSF contrast to about 10 5 in the central arcsecond. On nearby stars, this level is far from the theoretical PSF contrast limit imposed by photon noise in the wavefront sensor. A comparative study between wavefront sensing strategies shows that a focal-plane based wavefront sensor (WFS), combining wavefront sensing and scientific imaging on the same detector, seems optimal for high contrast imaging. This approach combines high WFS sensitivity, immunity to aliasing, chromaticity, and non common path errors and optical design simplicity. We show that such a system can be efficiently used as a second stage "Extreme-AO" system after a low-order AO system. The images acquired by the science camera are then used to drive the high-order DM (which also introduces the phase diversity needed for focal plane wavefront sensing). This scheme offers much flexibility, with the proper DM updates, the focal plane images can be simultaneously used to solve for the entrance wavefront and the presence of companions (which are incoherent with the speckles) below the speckle noise level. Control and data reduction algorithms are presented, as well as possible optical designs incorporating a coronagraph. A laboratory demonstration of this technique is currently being done at Subaru Telescope with a 1024 actuators MEMs DM. This experiment serves as a prototype to plan and design a similar system for Subaru's upcoming HiCIAO instrument (near-IR coronagraphic imager for adaptive optics).
• Guyon, O., Pluzhnik, E. A., Kuchner, M. J., Collins, B., & Ridgway, S. T. (2006). Theoretical limits on extrasolar terrestrial planet detection with coronagraphs. Astrophysical Journal, Supplement Series, 167(1), 81-99.
  More info

  Abstract: Many high-contrast coronagraph designs have recently been proposed. In this paper, their suitability for direct imaging of extrasolar terrestrial planets is reviewed. We also develop a linear algebra based model of coronagraphy that can both explain the behavior of existing coronagraphs and quantify the coronagraphic performance limit imposed by fundamental physics. We find that the maximum theoretical throughput of a coronagraph is equal to 1 minus the nonaberrated noncoronagraphic PSF of the telescope. We describe how a coronagraph reaching this fundamental limit may be designed, and how much improvement over the best existing coronagraph design is still possible. Both the analytical model and numerical simulations of existing designs also show that this theoretical limit rapidly degrades as the source size is increased: the "highest performance" coronagraphs, those with the highest throughput and smallest inner working angle (IWA), are the most sensitive to stellar angular diameter. This unfortunately rules out the possibility of using a small IWA (
• Guyon, O., Pluzhnik, E. A., Ridgway, S., & Woodruff, R. A. (2006). Imaging extrasolar terrestrial planets from Space with a PIAA coronagraph. Proceedings of SPIE - The International Society for Optical Engineering, 6265 I.
  More info

  Abstract: The Phase-Induced Amplitude Apodization Coronagraph (PIAAC) uses a lossless beam apodization, performed by aspheric mirrors, to produce a high contrast PSF. This concept offers a unique combination of high throughput (almost 100%), high angular resolution (λ/D), small inner working angle (IWA = 1.5 λ/D), excellent achromaticity (the apodization is performed by geometric reflection on mirrors) and low sensitivity to pointing errors or stellar angular diameter. These characteristics make the PIAAC an ideal choice for direct imaging of extrasolar terrestrial planets (ETPs) from space. We quantify the performance of the PIAAC and other coronagraph designs both in terms of "raw" coronagraphic performance (throughput, IWA etc...) and number of stars around which extrasolar terrestrial planets (ETPs) can be observed. We also identify the fundamental performance limit that can be achieved by coronagraphy, and show that no other coronagraph design is as close to this limit as the PIAAC. We find that in the photon noise limited regime, a 4m telescope with a PIAA coronagraph is able to detect Earth-like planets around 30 stars with Ihr exposure time per target (assuming 25% throughput and exozodi levels similar to our solar system). With a smaller 1 to 2-m diameter telescope, more massive rocky planets could be detected in the habitable zones of a few nearby stars, and an imaging survey of Jupiter-like planets could be performed. Laboratory results and detailed simulations confirm the large potential of this concept for direct imaging of ETPs. A prototype high contrast PIAAC system is currently being operated to demonstrate the coronagraph's performance.
• Guyon, O., Pluzhnik, E., Kuchner, M., Collins, B., & Ridgway, S. (2006). Theoretical Limits on Extrasolar Terrestrial Planet Detection with Coronagraphs. \apjs, 167(1), 81-99.
• Guyon, O., Sanders, D. B., & Stockton, A. (2006). Near-infrared adaptive optics imaging of QSO host galaxies. Astrophysical Journal, Supplement Series, 166(1), 89-127.
  More info

  Abstract: We report near-infrared (primarily H band) adaptive optics (AO) imaging with the Gemini-N and Subaru Telescopes, of a representative sample of 32 nearby (z < 0.3) QSOs selected from the Palomar-Green (PG) Bright Quasar Survey (BQS), in order to investigate the properties of the host galaxies. Two-dimensional modeling and visual inspection of the images shows that ∼36% of the hosts are ellipticals, ∼39% contain a prominent disk component, and ∼25% are of undetermined type. Thirty percent show obvious signs of disturbance. The mean MH(host) = -24.82 (2.1L H*), with a range -23.5 to -26.5 (∼0.63Z, H*, to 10L H*). At 2L H* most are ellipticals. "Disturbed" hosts are found at all M H(host), while "strongly disturbed" hosts appear to favor the more luminous hosts. Hosts with prominent disks have less luminous QSOs, while the most luminous QSOs are almost exclusively in ellipticals or in mergers (which presumably shortly will be ellipticals). At z < 0.13, where our sample is complete at B band, we find no clear correlation between M B(QSO) and M H(host). However, at z > 0.15, the more luminous QSOs (M B < -24.7), and four of five of the radio-loud QSOs, have the most luminous H-band hosts (>7L H*) , most of which are ellipticals. Finally, we find a strong correlation between the "infrared excess," L IR/L BB, of QSOs with host type and degree of disturbance. Disturbed and strongly disturbed hosts and hosts with dominant disks have L IR/L BB twice that of nondisturbed and elliptical hosts, respectively. QSOs with disturbed and strongly disturbed hosts are also found to have morphologies and mid/far-infrared colors that are similar to what is found for "warm" ultraluminous infrared galaxies, providing further evidence for a possible evolutionary connection between both classes of objects. © 2006, The American Astronomical Society. All rights reserved.
• Guyon, O., Sanders, D. B., & Stockton, A. N. (2006). Near-infrared AO imaging of QSO host galaxies. New Astronomy Reviews, 50(9-10), 748-753.
  More info

  Abstract: We report NIR (primarily H-band) AO imaging with the Gemini-N and Subaru telescopes, of 32 nearby (z < 0.3) QSOs selected from the Palomar-Green bright quasar survey (PGBQS), in order to investigate the properties of the host galaxies. Two-dimensional modeling and visual inspection of the images shows that ∼36% of the hosts are ellipticals, ∼39% contain a prominent disk component, and ∼25% are of undetermined type. Thirty percent show obvious signs of disturbance. The mean MH(host) = -24.82 (2.1 LH*), with a range -23.5 to -26.5. At < LH*, all hosts have a dominant disk component, while at > 2 LH* most are ellipticals. "Disturbed" hosts are found at all MH(host). Hosts with prominent disks have less luminous QSOs, while the most luminous QSOs are almost exclusively in ellipticals or in mergers (which presumably shortly will be ellipticals). There is a strong correlation between the "infrared-excess", LIR/LBB, of QSOs with host type and degree of disturbance. Disturbed and strongly disturbed hosts and hosts with dominant disks have LIR/LBB twice that of non-disturbed and elliptical hosts, respectively. © 2006 Elsevier B.V. All rights reserved.
• Guyon, O., Sanders, D., & Stockton, A. (2006). Near-Infrared Adaptive Optics Imaging of QSO Host Galaxies. \apjs, 166(1), 89-127.
• Guyon, O., Sanders, D., & Stockton, A. (2006). Near-infrared AO imaging of QSO host galaxies. \nar, 50(9-10), 748-753.
• Hattori, M., Golota, T., Olivier, G., Dinkins, M., Oya, S., Colley, S., Eldred, M., Watanabe, M., Itoh, M., Saito, Y., Hayano, Y., Takami, H., & Iye, M. (2006). Implementation of modal optimization system of Subaru-188 adaptive optics. Proceedings of SPIE - The International Society for Optical Engineering, 6272 III.
  More info

  Abstract: Subaru AO-188 is a curvature adaptive optics system with 188 elements. It has been developed by NAOJ (National Astronomical Observatory of Japan) in recent years, as the up grade from the existing 36-element AO system currently in operation at Subaru telescope. In this upgrade, the control scheme is also changed from zonal control to modal control. This paper presents development and implementation of the modal optimization system for this new AO-188. Also, we will introduce some special features and attempt in our implementation, such as consideration of resonance of deformable mirror at the lower order modes, and extension of the scheme for the optimization of the magnitude of membrane mirror in wave front sensor. Those are simple but shall be useful enhancement for the better performance to the conservative configuration with conventional modal control, and possibly useful in other extended operation modes or control schemes recently in research and development as well.
• Hayano, Y., Saito, Y., Ito, M., Saito, N., Kato, M., Akagawa, K., Takazawa, A., Colley, S. A., Dinkins, M. C., Eldred, M., Golota, T. I., Guyon, O., Hattori, M., Oya, S., Watanabe, M., Takami, H., Wada, S., & Iye, M. (2006). The laser guide star facility for Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 6272 III.
  More info

  Abstract: The purpose of this paper is to report on the current status of developing the new laser guide star (LGS) facility for the Subaru LGS adaptive optics (AO) system. Since two major R&D items, the 4W-class sum-frequency generating laser1 and the large-area-core photonic crystal fiber,2have been successfully cleared, we are almost ready to install the LGS facility to the Subaru Telescope. Also we report the result for LGS generation in Japan.
• Hodapp, K. W., Tamura, M., Suzuki, R., Jacobson, S., Stahlberger, V., Yamada, H., Takami, H., Guyon, O., & Abe, L. (2006). Design of the HiCIAO instrument for the subaru telescope. Proceedings of SPIE - The International Society for Optical Engineering, 6269 II.
  More info

  Abstract: HiCIAO, the High-Contrast Coronographic Imager for Adaptive Optics, is a coronographic simultaneous differential imager for the Subaru Telescope Nasmyth focus. It is designed primarily to search for faint companions, brown dwarves and young giant planets, around nearby stars, but will also allow observations of disks around young stars and of emission line regions near other bright central sources. HiCIAO will work in conjunction with the new Subaru Telescope 188 actuator adaptive optics system. It is designed as a flexible, experimental instrument that will grow from the initial, simple coronographic system into more complex, innovative coronographic optics as these technologies become available. The main component of HiCIAO is an infrared camera optimized for spectral simultaneous differential imaging that uses a 2.5 μm HAWAII-2RG detector array operated by a Rockwell Sidecar AS1C.
• Ito, M., Hayano, Y., Saito, N., Akagawa, K., Kato, M., Saito, Y., Takazawa, A., Takami, H., Iye, M., Wada, S., Colley, S. A., Dinkins, M. C., Eldred, M., Golota, T. I., Guyon, O., Hattori, M., Oya, S., & Watanabe, M. (2006). Transmission characteristics of high-power 589-nm laser beam in photonic crystal fiber. Proceedings of SPIE - The International Society for Optical Engineering, 6272 III.
  More info

  Abstract: We are developing Laser Guide Star Adaptive Optics (LGSAO) system for Subaru Telescope at Hawaii. Mauna Kea. We achieved an all-solid-state 589.159 nm laser in sum-frequency generation. Output power at 589.159 nm reached 4W in quasi-continuous-wave operation. To relay the laser beam from laser location to laser launching telescope, we used an optical fiber because the optical fiber relay is more flexible and easier than mirror train. However, nonlinear scattering effect, especially stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS), will happen when the inputted laser power increases, i.e., intensity at the fiber core exceed each threshold. In order to raise the threshold levels of each nonlinear scattering, we adopt photonic crystal fiber (PCF). Because the PCF can be made larger core than usual step index fiber (SIF), one can reduce the intensity in the core. We inputted the high power laser into the PCF whose mode field diameter (MFD) is 14 μm and the SIF whose MFD is 5 μm, and measured the transmission characteristics of them. In the case of the SIF, the SRS was happen when we inputted 2 W. On the other hand, the SRS and the SBS were not induced in the PCF even for an input power of 4 W. We also investigated polarization of the laser beam transmitting through the PCF. Because of the fact that the backscattering efficiency of exciting the sodium layer with a narrowband laser is dependent on the polarization state of the incident beam, we tried to control the polarization of the laser beam transmitted the PCF. We constructed the system which can control the polarization of input laser and measure the output polarization. The PCF showed to be able to assume as a double refraction optical device, and we found that the output polarization is controllable by injecting beam with appropriate polarization through the PCF. However, the Laser Guide Star made by the beam passed through the PCF had same brightness as the state of the polarization.
• Martinache, F., & Guyon, O. (2006). Performance of a phase induced amplitude apodization coronograph. EAS Publications Series, 22, 281-289.
  More info

  Abstract: This paper exposes a method for evaluating the performances of a system dedicated to exoplanet direct imaging. It is based on the use of a statistical description of a somewhat ideal star/planet couple in terms of contrast and angular separation. Among many already available techniques, the Phase Induced Amplitude Apodization Coronagraph (PIAAC) seems to gather all the necessary qualities to perform direct imaging of hypothetical Earth-like exoplanets in the close Solar neighbourhood (30 pc). After a quick description of its concept, the proposed evaluation method is used and provides an original set of criteria to classify concepts. © EAS, EDP Sciences 2006.
• Martinache, F., Guyon, O., Pluzhnik, E. A., Galicher, R., & Ridgway, S. T. (2006). Exoplanet Imaging with a Phase-induced Amplitude Apodization Coronograph. II. Performance. \apj, 639(2), 1129-1137.
• Martinache, F., Guyon, O., Pluzhnik, E. A., Galicher, R., & Ridgway, S. T. (2006). Exoplanet imaging with a phase-induced amplitude apodization coronograph. II. Performance. Astrophysical Journal Letters, 639(2 I), 1129-1137.
  More info

  Abstract: The phase-induced amplitude apodization coronagraph (PIAAC) uses a lossless achromatic apodization of the telescope pupil to produce a coronagraphic image without compromising the throughput and angular resolution of the telescope. Whereas the principle of the PIAAC concept was discussed in a previous paper, the purpose of this work is to provide an exhaustive analysis of the expected performances of a PIAAC on a 4 m diameter telescope in space. Results presented here are based on realistic simulations of extrasolar terrestrial planets (ETPs) orbiting F, G, K, and M stars within 30 pc of the solar system and take into account the probability distributions of planet phase and angular separation. We show that a quasi-complete detection survey of 100 stars (with six observations per star) would require about 2 days of "open shutter" observing time in the ideal system considered in this work (4 m telescope, 100% throughput). A classical apodizer would require exposure times about 100 times longer than PIAAC on a Sun-Earth system at 10 pc. Small pointing errors and non-monochromatic observing require slight oversizing of the focal plane mask with little impact on the system performance. © 2006. The American Astronomical Society. All rights reserved.
• Oya, S., Bouvier, A., Guyon, O., Watanabe, M., Hayano, Y., Takami, H., Iye, M., Hattori, M., Saito, Y., Itoh, M., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2006). Performance of the deformable mirror for Subaru LGSAO. Proceedings of SPIE - The International Society for Optical Engineering, 6272 III.
  More info

  Abstract: The performance of a deformable mirror with 188 electrodes is reported in this paper. The deformable mirror has been manufactured by CILAS for a new adaptive optics system at Subaru Telescope equipped with laser-guide-star. The type of deformable mirror is bimorph PZT with the blank diameter of 130 mm (beam size 90 mm).
• Perrin, G., Woillez, J., Lai, O., Gu{\'erin}, J., Kotani, T., Wizinowich, P., Le Mignant, D., Hrynevych, M., Gathright, J., L{\'ena}, P., Chaffee, F., Vergnole, S., Delage, L., Reynaud, F., Adamson, A., Berthod, C., Brient, B., Collin, C., Cr{\'etenet}, J., , Dauny, F., et al. (2006). Interferometric coupling of the Keck telescopes with single-mode fibers. Science, 311, 194.
• Perrin, G., Woillez, J., Lai, O., Guérin, J., Kotani, T., Wizinowich, P. L., Mignant, D. L., Hrynevych, M., Gathright, J., Léna, P., Chaffee, F., Vergnole, S., Delage, L., Reynaud, F., Adamson, A. J., Berthod, C., Brient, B., Collin, C., Crétenet, J., , Dauny, F., et al. (2006). Interferometric coupling of the Keck telescopes with single-mode fibers. Science, 311(5758), 194-.
• Pluzhnik, E. A., Guyon, O., Ridgway, S. T., Martinache, F., Woodruff, R. A., Blain, C., & Galicher, R. (2006). Exoplanet Imaging with a Phase-induced Amplitude Apodization Coronagraph. III. Diffraction Effects and Coronagraph Design. \apj, 644(2), 1246-1257.
• Pluzhnik, E. A., Guyon, O., Ridgway, S. T., Martinache, F., Woodruff, R. A., Blain, C., & Galicher, R. (2006). Exoplanet imaging with a phase-induced amplitude apodization coronagraph. III. Diffraction effects and coronagraph design. Astrophysical Journal, 644(2 II), 1246-1257.
  More info

  Abstract: Properly apodized pupils can deliver point-spread functions (PSFs) free of Airy rings and are suitable for high dynamical range imaging of extrasolar terrestrial planets (ETPs). To reach this goal, classical pupil apodization (CPA) unfortunately requires most of the light gathered by the telescope to be absorbed, resulting in poor throughput and low angular resolution. Phase-induced amplitude apodization (PIAA) of the telescope pupil combines the advantages of classical pupil apodization (particularly low sensitivity to low-order aberrations) with full throughput, no loss of angular resolution and little chromaticity, which makes it, theoretically, an extremely attractive coronagraph for direct imaging of ETPs. The two most challenging aspects of this technique are (1) the difficulty of polishing the required optics shapes and (2) diffraction propagation effects, which, because of their chromaticity, can decrease the spectral bandwidth of the coronagraph. We show that a properly designed hybrid system combining classical apodization with the PIAA technique can solve both problems simultaneously. For such a system, the optics shapes can be well within today's optics manufacturing capabilities, and the 10 -10 PSF contrast at ≈ 1.5Λ/D required for efficient imaging of ETPs can be maintained over the whole visible spectrum. This updated design of the PIAA coronagraph maintains the high performance of the earlier design, since only a small part of the light is lost in the classical apodizer(s). © 2006. The American Astronomical Society. All rights reserved.
• Pluzhnik, E., Guyon, O., Warren, M., Ridgway, S. T., & Woodruff, R. A. (2006). PIAA coronagraph design: System optimization and first optics testing. Proceedings of SPIE - The International Society for Optical Engineering, 6265 II.
  More info

  Abstract: An optical system capable of extremely high contrast imaging (about 10 -10) at separations comparable to the telescope's diffraction limit is critical for direct imaging of extrasolar terrestrial planets. The PIAA coronagraph (Guyon 2003) based on pupil apodization by geometrical remapping of the flux in the pupil plane seems to be especially adopted for the exoplanet imaging. Although this technique combines many of the advantages found separately in other coronagraphs, two serious concerns remain unanswered: optics manufacturability and effects of diffraction propagation. We describe here a hybrid PIAA/CPA (Classical Pupil Apodization) design in which the apodization is shared between a remapping system (the main apodizer) and "classical" apodizers (auxiliary apodizers). In this scheme, optics become easier to manufacture and diffraction effects can be decreased to a level consistent with a 10-10 PSF contrast in a wide spectral band. We show how the parameters of hybrid PIAA/CPA system can be optimized and present some results of optical testing for the high optical quality prototype of PIAA coronagraph.
• Saito, Y., Hayano, Y., Saito, N., Akagawa, K., Takazawa, A., Kato, M., Ito, M., Colley, S., Dinkins, M., Eldred, M., Golota, T., Guyon, O., Hattori, M., Oya, S., Watanabe, M., Takami, H., Iye, M., & Wada, S. (2006). 589 nm sum-frequency generation laser for the LGS/AO of Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 6272 III.
  More info

  Abstract: We developed a high power and high beam quality 589 nm coherent light source by sum-frequency generation in order to utilize it as a laser guide star at the Subaru telescope. The sum-frequency generation is a nonlinear frequency conversion in which two mode-locked Nd:YAG lasers oscillating at 1064 and 1319 nm mix in a nonlinear crystal to generate a wave at the sum frequency. We achieved the qualities required for the laser guide star. The power of laser is reached to 4.5 W mixing 15.65 W at 1064 nm and 4.99 W at 1319 nm when the wavelength is adjusted to 589.159 nm. The wavelength is controllable in accuracy of 0.1 pm from 589.060 and 589.170 nm. The stability of the power holds within 1.3% during seven hours operation. The transverse mode of the beam is the TEM00 and M2 of the beam is smaller than 1.2. We achieved these qualities by the following technical sources; (1) simple construction of the oscillator for high beam quality, (2) synchronization of mode-locked pulses at 1064 and 1319 nm by the control of phase difference between two radio frequencies fed to acousto-optic mode lockers, (3) precise tunability of wavelength and spectral band width, and (4) proper selection of nonlinear optical crystal. We report in this paper how we built up each technical source and how we combined those.
• Takami, H., Colley, S., Dinkins, M., Eldred, M., Guyon, O., Golota, T., Hattori, M., Hayano, Y., Ito, M., Iye, M., Oya, S., Saito, Y., & Watanabe, M. (2006). Status of Subaru laser guide star AO system. Proceedings of SPIE - The International Society for Optical Engineering, 6272 I.
  More info

  Abstract: The laser guide star adaptive optics (AO188) system for Subaru Telescope is presented. The system will be installed at the IR Nasmyth platform of Subaru 8 m telescope, whereas the current AO system with 36 elements is operating at the Cassegrain focus. The new AO system has a 188 element wavefront curvature sensor with photon counting APD modules and 188 element bimorph mirror. The laser guide star system has a 4.5 W solid state sum-frequency laser on the Nasmyth platform. The laser launching telescope with 50 cm aperture will be installed at behind the secondary mirror. The laser beam will be transferred to the laser launching telescope using photonic crystal single mode fiber cable. The instrument with the AO system is IRCS, infrared camera and spectrograph which has been used for Cassegrain AO system and new instrument, HiCIAO, high dynamic range infrared camera for exsolar planet detection. The first light of the AO system is planned in 2006.
• Tamura, M., Hodapp, K., Takami, H., Abe, L., Suto, H., Guyon, O., Jacobson, S., Kandori, R., Morino, J., Murakami, N., Stahlberger, V., Suzuki, R., Tavrov, A., Yamada, H., Nishikawa, J., Ukita, N., Hashimoto, J., Izumiura, H., Hayashi, M., , Nakajima, T., et al. (2006). Concept and science of HiCIAO: High contrast instrument for the Subaru next generation adaptive optics. Proceedings of SPIE - The International Society for Optical Engineering, 6269 I.
  More info

  Abstract: Direct exploration of exoplanets is one of the most exciting topics in astronomy. Our current efforts in this field are concentrated on the Subaru 8. 2m telescope at Mauna Kea, Hawaii. Making use of the good observing site and the excellent image quality, the infrared coronagraph CIAO (Coronagraphic Imager with Adaptive Optics) has been used for various kinds of surveys, which is the first dedicated cold coronagraph on the 8-10m class telescopes. However, its contrast is limited by the low-order adaptive optics and a limited suppression of the halo speckle noise. HiCIAO is a new high-contrast instrument for the Subaru telescope. HiCIAO will be used in conjunction with the new adaptive optics system (188 actuators and/or its laser guide star - AO188/LGSAO188) at the Subaru infrared Nasmyth platform. It is designed as a flexible camera comprising several modules that can be configured into different modes of operation. The main modules are the AO module with its future extreme AO capability, the warm coronagraph module, and the cold infrared camera module. HiCIAO can combine coronagraphic techniques with either polarization or spectral simultaneous differential imaging modes. The basic concept of such differential imaging is to split up the image into two or more images, and then use either different planes of polarization or different spectral filter band-passes to produce a signal that distinguishes faint objects near a bright central object from scattered halo or residual speckles. In this contribution, we will outline the HiCIAO instrument, its science, and performance simulations. The optical and mechanical details are described by Hodapp et al. (2006) 1. We also present a roadmap of Japanese facilities and future plans, including ASTRO-F (AKARI), SPICA, and JTPF, for extrasolar planet explorations.
• Galicher, R., Guyon, O., Otsubo, M., Suto, H., & Ridgway, S. (2005). Laboratory Demonstration and Numerical Simulations of the Phase-Induced Amplitude Apodization. \pasp, 117(830), 411-420.
• Galicher, R., Guyon, O., Otsubo, M., Suto, H., & Ridgway, S. (2005). Laboratory demonstration and numerical simulations of the phase-induced amplitude apodization. Publications of the Astronomical Society of the Pacific, 117(830), 411-420.
  More info

  Abstract: Phase-induced amplitude apodization (PIAA) uses two aspheric optics to produce an achromatic apodization of an incoming beam by changing the geometrical distribution of the light in the pupil plane. Since this apodization is lossless, the sensitivity and angular resolution of the telescope are preserved, theoretically allowing efficient detection of Earth-size planets from space with a 2 m diameter optical telescope. In this paper, we report the first laboratory demonstration of imaging with a PIAA system. First, we show that the optics shapes computed by our algorithm produce an apodized collimated beam only by changing the geometrical distribution of the light and without losing light. We then present images of on- and off-axis point-spread functions and compare them with our numerical simulations. © 2005. The Astronomical Society of the Pacific. All rights reserved.
• Guyon, O. (2005). High Contrast Adaptive Optics for Exoplanet Detections: Performance limits and optimal wavefront sensing strategy. Proceedings of the International Astronomical Union, 1, 559-564.
  More info

  Abstract: The effects of photon noise, aliasing, wavefront chromaticity and scintillation on the PSF contrast achievable by ground-based adaptive optics (AO) are evaluated for different wavefront sensing schemes. I show that "classical" AO (sensing in the visible, imaging in the near-IR) is limited to about 105 PSF contrast in the central arcsecond because of scintillation chromaticity. This comparative study shows that a focal-plane based wavefront sensor (WFS), combining wavefront sensing and scientific imaging on the same detector is optimal for high contrast imaging. This approach combines high WFS sensitivity, immunity to aliasing and non common path errors and optical design simplicity. Its theoretical performance is compared to commonly used WFSs, illustrating the advantages of this technique. I show that such a system can be efficiently used as a second stage after a low-order AO system. Control and data reduction algorithms are presented, as well as possible optical designs incorporating a coronagraph. A laboratory demonstration of this technique is currently being done at Subaru Telescope. © 2006 International Astronomical Union.
• Guyon, O. (2005). Limits of Adaptive Optics for High-Contrast Imaging. \apj, 629(1), 592-614.
• Guyon, O. (2005). Limits of adaptive optics for high-contrast imaging. Astrophysical Journal Letters, 629(1 I), 592-614.
  More info

  Abstract: The effects of photon noise, aliasing, wave front chromaticity, and scintillation on the point-spread function (PSF) contrast achievable with ground-based adaptive optics (AO) are evaluated for different wave front sensing schemes. I show that a wave front sensor (WFS) based on the Zernike phase contrast technique offers the best sensitivity to photon noise at all spatial frequencies, while the Shack-Hartmann WFS is significantly less sensitive. In AO systems performing wave front sensing in the visible and scientific imaging in the near-IR, the PSF contrast limit is set by the scintillation chromaticity induced by Fresnel propagation through the atmosphere. On an 8 m telescope, the PSF contrast is then limited to 10 -4 to 10-5 in the central arcsecond. Wave front sensing and scientific imaging should therefore be done at the same wavelength, in which case, on bright sources, PSF contrasts between 10-6 and 10 -7 can be achieved within 1″ on an 8 m telescope in optical/near-IR. The impact of atmospheric turbulence parameters (seeing, wind speed, turbulence profile) on the PSF contrast is quantified. I show that a focal plane wave front sensing scheme offers unique advantages, and I discuss how to implement it. Coronagraphic options are also briefly discussed. © 2005. The American Astronomical Society. All rights reserved.
• Guyon, O., Pluzhnik, E. A., Galicher, R., Martinache, F., Ridgway, S. T., & Woodruff, R. A. (2005). Exoplanet Imaging with a Phase-induced Amplitude Apodization Coronagraph. I. Principle. \apj, 622(1), 744-758.
• Guyon, O., Pluzhnik, E. A., Galicher, R., Martinache, F., Ridgway, S. T., & Woodruff, R. A. (2005). Exoplanet imaging with a phase-induced amplitude apodization coronagraph. I. Principle. Astrophysical Journal Letters, 622(1 I), 744-758.
  More info

  Abstract: Using two aspheric mirrors, it is possible to apodize a telescope beam without losing light or angular resolution: the output beam is produced by "remapping" the entrance beam to produce the desired light intensity distribution in a new pupil. We present the phase-induced amplitude apodization coronagraph (PIAAC) concept, which uses this technique, and show that it allows efficient direct imaging of extrasolar terrestrial planets with a small-sized telescope in space. The suitability of the PIAAC for exoplanet imaging is due to a unique combination of achromaticity, small inner working angle (about 1.5λ/d), high throughput, high angular resolution, and large field of view. Three-dimensional geometrical ray tracing is used to investigate the off-axis aberrations of PIAAC configurations and show that a field of view of more than 100λ/d in radius is available thanks to the correcting optics of the PIAAC, Angular diameter of the star and tip-tilt errors can be compensated for by slightly increasing the size of the occulting mask in the focal plane, with minimal impact on the system performance. Earth-sized planets at 10 pc can be detected in less than 30 s with a 4 m telescope. Wave-front quality requirements are similar to classical techniques. © 2005. The American Astronomical Society. All rights reserved.
• Guyon, O., Pluzhnik, E. A., Ridgway, S. T., Woodruff, R. A., Blain, C., Martinache, F., & Galicher, R. (2005). The Phase-Induced Amplitude Coronagraph (PIAA). Proceedings of the International Astronomical Union, 1, 385-391.
  More info

  Abstract: The Phase-Induced Amplitude Coronagraph (PIAAC) uses a lossless beam apodization, performed by aspheric mirrors, to produce a high contrast PSF. Thanks to the lossless apodization, this concept offers a unique combination of high theoretical throughput (≈100%), high angular resolution (λ/d), small inner working angle (≈1.5λ/d), low chromaticity and low sensitivity to pointing errors or angular star diameter. Together, these characteristics make the PRC an ideal choice for direct imaging of extrasolar terrestrial planets (ETPs) from space. We show that a visible telescope smaller than 4m would then achieve the goals of the TPF mission, while other coronagraphs considered for TPF require telescope diameters typically 2 to 3 times larger. On a large size (8m) space telescope, ETPs can be searched for around a significantly larger sample of stars, thus enabling a much higher scientific return. © 2006 International Astronomical Union.
• Pluzhnik, E. A., Guyon, O., Ridgway, S., Woodruff, R., Blain, C., Martinache, F., & Galicher, R. (2005). The phase induced amplitude apodization coronagraph: An overview of simulations and laboratory effort. Proceedings of the International Astronomical Union, 1, 489-494.
  More info

  Abstract: The high contrast (typically 1010) and small angular separation between a planet and its parent star are the main challenges that need to be overcome to detect and characterize Earth-like planets around the nearest stars. Therefore, exoplanet imaging requires the use of a coronagraph, that ideally efficiently cancels the light from the star and has minimal influence on the planet image. The Phase Induced Amplitude Apodization Coronagraph relies on pupil apodization by geometrical remapping of the flux in the pupil plane. This method combines the advantages of classical pupil apodization with high throughput (≈100%) and high angular resolution (≈λ/D), and has some unique advantages over most coronagraphs, such as low chromaticity, low sensitivity to stellar angular size and to small pointing errors. As a result, planet detection time is about 50-100 times shorter in comparison with classical coronagraphic techniques (Martinache et al. 2005). Both the advantages of the PIAAC and the main factors affecting the performance of the coronograph will be examined in our laboratory experiment in which high quality PIAA optics wilkl be combined with wavefront control to demonstrate achromatic high contrast imaging (10 6 or more) at small angular separation (less than 2λ/D). We present here a description and current status of this experiment together with a short analyses of the main factors affecting the performance of the coronograph. © 2006 International Astronomical Union.
• Pluzhnik, E., Guyon, O., Ridgway, S., Martinache, F., Woodruff, R., Blain, C., & Galicher, R. (2005). Exoplanet Imaging with a Phase-induced Amplitude Apodization Coronagraph III. Hybrid Approach: Optical Design and Diffraction Analysis. arXiv e-prints, astro-ph/0512421.
• Guyon, O. (2004). Coronagraphy VS. nulling. EAS Publications Series, 12, 263-271.
  More info

  Abstract: Nulling cancels out the light of a source by destructive interference between several beams, while coronagraphy is a much larger family of high dynamical range imaging techniques designed for single pupil telescopes. In this paper, nulling techniques and three different classes of coronagraphs are compared using criteria relevant to the detection of Earth-sized planets around nearby stars. © EAS, EDP Sciences 2004.
• Guyon, O. (2004). Imaging Faint Sources within a Speckle Halo with Synchronous Interferometric Speckle Subtraction. \apj, 615(1), 562-572.
• Guyon, O. (2004). Imaging faint sources within a speckle halo with synchronous interferometric speckle subtraction. Astrophysical Journal Letters, 615(1 I), 562-572.
  More info

  Abstract: The performance of high-contrast imaging systems is very often limited by the presence of speckles in the point-spread function (PSF) of the central source. Since this unwanted light is coherent with the central source, it is possible to make it interfere with light extracted from the center of the PSF. The light of a faint companion, however, will not interfere with the central source. By taking advantage of this fundamental difference, it is possible to detect faint companions superposed on speckles more than 100 times brighter, even if the speckles are rapidly "boiling." Possible optical designs to use this technique on interferometers or imaging telescopes are shown, and a data analysis algorithm is proposed. Synchronous interferometric speckle suppression greatly improves the performance of ground-based telescopes with adaptive optics systems for direct imaging of faint companions. On a space telescope, where the speckle lifetime is expected to be longer, companions 104 times fainter than the speckle halo can be detected in a few minutes.
• Guyon, O. (2004). Pupil remapping techniques for high dynamical range imaging. EAS Publications Series, 12, 11-20.
  More info

  Abstract: Telescope pupils are usually not well suited for high dynamical range imaging. Central obstruction, telescope spiders, hard edges and sparseness (for interferometers) can make it very challenging to build a coronagraph. Fortunately, it is often possible to remap a telescope pupil to achieve high contrast imaging without loosing light. In the case of a monolithic telescope, pupil remapping can produce an apodized pupil with 2 aspheric mirrors which redistribute the light without introducing phase aberrations. Similarly, an interferometer pupil can be remapped into a tight configuration compatible with coronagraphic techniques. © EAS, EDP Sciences 2004.
• Guyon, O. (2004). Synchronous interferometric speckle subtraction (SISS): A concept to remove speckle noise in adaptive optics imaging and interferometry. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 2), 593-601.
  More info

  Abstract: In PSFs obtained by AO systems, a cloud of speckles is surrounding the central diffraction core. These speckles don't average in time, and are extremely difficult to calibrate by the observation of a reference star. This "speckle noise" is setting the detection limit of faint companions around bright stars far above the photon noise. Speckles are coherent with the central diffraction core of the PSF, while a faint companion is not. By inducing interferences between the speckle cloud and a reference wave extracted from the central core of the PSF, it is possible to take advantage of this fundamental difference to identify and subtract the speckles. A time-variable phase delay is introduced in the reference wave in order to rapidly modulate the intensity of the speckles. The amplitude of this modulation leads to an accurate measure of the speckle intensity, which can then be subtracted to the image. This technique, which is compatible with spectroscopy, allows efficient detection of companions about 1000 times fainter than the speckles, and is especially attractive for exoplanet searches. The same technique can also be used on interferometers.
• Guyon, O., Arimoto, N., Blain, C., Colley, S., Eldred, M., Goto, M., Hattori, M., Hayano, Y., Iye, M., Kamata, Y., Kane, T., Kobayashi, N., Watanabe, M., Minowa, Y., Oya, S., Saito, Y., Takami, H., & Takato, N. (2004). Subaru Telescope LGSAO: Overview of expected performance. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 2), 733-741.
  More info

  Abstract: The Subaru Telescope LGSAO system is a 188 elements curvature AO system currently under construction, and scheduled to have first light in March 2006 for the Natural Guide Star mode and March 2007 for the Laser Guide Star mode. A particularity of this system will be to perform curvature wavefront sensing with several extra-pupil distances, which significantly improves the closed-loop performance. An overview of the predicted performance of the system is given for Natural Guide Star and Laser Guide Star modes.
• Guyon, O., Ridgway, S., Aime, C., Boccaletti, A., Beuzit, J., Galicher, R., Kern, P., Kotani, T., Lagrange, A., Lyon, R., Malbet, F., Murakawa, K., Otsubo, M., Rouan, D., Soummer, R., Suto, H., Tamura, M., & Woodruff, R. (2004). Pupil Remapping Coronagraph (PRC): A high performance coronagraph for a small-size visible terrestrial planet finder. Proceedings of SPIE - The International Society for Optical Engineering, 5487(PART 3), 1304-1311.
  More info

  Abstract: Amplitude apodization of a telescope's pupil can be used to reduce the diffraction rings (Airy rings) in the PSF to allow high contrast imaging. Rather than achieving this apodization by selectively removing light at the edges of the pupil, we propose to produce the desired apodized pupil by redistributing the pupil's light. This lossless apodization concept can yield a high contrast PSF which allows the efficient detection of Earth-sized planets around stars at 10pc with a 2m visible telescope in space. We review the current status of a JPL-funded study of this concept for the Terrestrial Planet Finder (TPF) mission, including a lab experiment and extensive computer simulations.
• Hayano, Y., Saito, Y., Saito, N., Akagawa, K., Kamata, Y., Kanzawa, T., Kurakami, T., Takato, N., Colley, S., Eldred, M., Kane, T., Guyon, O., Oya, S., Watanabe, M., Hattori, M., Golota, T., Dinkins, M., Kobayashi, N., Minowa, Y., , Goto, M., et al. (2004). Design of laser system for subaru LGS AO. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 3), 1088-1095.
  More info

  Abstract: We present the development status of the laser system for Subaru Laser Guide Star Adaptive Optics System. We are manufacturing the quasi-continuous-wave sum frequency laser as a prototype. The optical efficiency of sum frequency generation normalized by the mode-locked fundamental YAG (1064 nm) laser output power is achieved to be 14 % using the non-linear crystal, periodically poled potassium titanyl phosphate (PPKTP). Output power at sodium D2 line was about 260 mW. The optical relay fiber and the laser launching telescope are also described in this paper. For the optical relay fiber, we are testing an index guided photonic crystal fiber (PCF), whose core material is filled by fused silica, and whose clad has close-packed air holes in two dimension. The coupling efficiency was evaluated as about 80 % using 1mW He-Ne laser. We introduce the design of laser launching telescope (LLT), which is a copy of VLT laser launching telescope, and the interface to the Subaru Telescope.
• Iye, M., Takami, H., Takato, N., Oya, S., Hayano, Y., Guyon, O., Colley, S., Hattori, M., Watanabe, M., Eldred, M., Saito, Y., Saito, N., Akagawa, K., & Wada, S. (2004). Cassegrain and Nasmyth Adaptive Optics systems of 8.2-m Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 5639, 1-10.
  More info

  Abstract: The performance of the Cassegrain Adaptive Optics (AO) system of the 8.2 m Subaru Telescope is reported. The system is based on a curvature wavefront sensor with 36 photon-counting avalanche photodiode modules and a bimorph wavefront correcting deformable mirror with 36 driving electrodes. This AO system has been in service since 2002 April for two open-use instruments, an infrared camera and spectrograph (IRCS) and a coronagraph imager with adaptive optics (CIAO). The Strehl ratio in the K-band is around 0.3 when a bright guide star is available under 0″.4 seeing condition. High sensitivity of the wavefront sensor allows significant improvement in the image quality, even for faint guide stars down to R = 18 mag. The design of the new Nasmyth Adaptive Optics system with 188 control elements under construction is described. This new system with fivefold increase in the number of control elements will provide twice higher Strehl ratio of 0.7. To increase the sky coverage for this new system, a power laser system to produce an artificail guide star in the upper atmosphere is also under construction. The AO system with laser guide capability enables the coverage up to 80% of the entire sky and offers diffraction limited observation for almost any target in the sky. An all solid-state 4W laser to generate the sodium D line emission by summing the two YAG laser frequencies is under development. The generated laser beam is tranmitted through a photonic crystal fiber to the laser launching telescope attached at the backside of the secondary mirror. Expected performance of this laser guide Nasmyth AO system is shown.
• Oya, S., Guyon, O., Watanabe, M., Hayano, Y., Takami, H., Iye, M., Arimoto, N., Colley, S., Eldred, M., Kane, T., Hattori, M., Saito, Y., Kamata, Y., Kobayashi, N., Minowa, Y., Goto, M., & Takato, N. (2004). Deformable mirror design of Subaru LGSAO system. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 3), 1546-1555.
  More info

  Abstract: As an upgrade plan of Subaru adaptive optics facility, laser-guide-star adaptive-optics (LGSAO) project is on going. One of key components of the project is a deformable mirror (DM). The DM for LGSAO is a bimorph type of PZT with 188 control elements. The specification of design is presented together with the analysis of stroke and vibration properties by FEM.
• Perrin, G., Lai, O., Woillez, J., Guerin, J., Kotani, T., Vergnole, S., Adamson, A. J., Ftaclas, C., Guyon, O., Léna, P., Nishikawa, J., Reynaud, F., Roth, K., Ridgway, S. T., Tokunaga, A. T., & Wizinowich, P. L. (2004). OHANA. Proceedings of SPIE - The International Society for Optical Engineering, 5491(PART 1), 391-404.
  More info

  Abstract: The Mauna Kea Observatory offers a unique opportunity to build a large and sensitive interferometer. Seven telescopes have diameters larger than 3 meters and are or may be equipped with adaptive optics systems to correct phase perturbations induced by atmospheric turbulence. The maximum telescope separation of 800 meters can provide an angular resolution as good as 0.25 milli-arcseconds in the J band. The large pupils and long baselines make 'OHANA very complementary to existing large optical interferometers. From an astrophysical point of view, it opens the way to imaging of the central part of faint and compact objects such as active galactic nuclei and young stellar objects. On a technical point of view, it opens the way to kilometric or more arrays by propagating light in single-mode fibers. First instruments have been built and tested successfully at CFHT, Keck I and Gemini to inject light into single-mode fibers thus partly completing Phase I of the project. Phase II is now on-going with the prospects of the first combinations of Keck I - Keck II in 2004 and Gemini - CFHT in 2005.
• Takami, H., Watanabe, M., Takato, N., Colley, S., Eldred, M., Kane, T., Guyon, O., Hattori, M., Goto, M., Iye, M., Hayano, Y., Kamata, Y., Arimoto, N., Kobayashi, N., & Minowa, Y. (2004). Laser guide star AO project at the Subaru Telescope. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 2), 837-845.
  More info

  Abstract: The laser guide star adaptive optics (AO) system for Subaru Telescope is presented. The system will be installed at the IR Nasmyth platform, whereas the current AO system with 36 elements is operating at the Cassegrain focus. The new AO system has a 188 element wavefront curvature sensor with photon counting APD modules which is the largest control element curvature sensor system ever. The system will have 4-10 W solid state sum-frequency laser to generate a laser guide star. The laser launching telescope with 50 cm aperture will be installed at behind the secondary mirror. The laser unit will be installed on the third floor of the dome and the laser beam will be transferred to the laser launching telescope using single mode photonic crystal fiber cable. The field of view of the optics is 2.7 arcmin to maximize the probability to find tilt guide stars for laser guide star operation. The expected Strehl ratio as raw AO performance is 0.46 at H-band under 0.60" seeing with 12 th mag guide star, and 0.71 for 8 th mag stars. New wavefront modulation technique, dual stroke membrane mirror control, is developed to reduce the tilt error which is more dominant for curvature sensor AO system. The superb contrast imaging capability will be expected as natural guide star system. The first light as the natural guide star system is planned in March 2006, the laser first light will be expected in March 2007.
• Watanabe, M., Takami, H., Takato, N., Colley, S., Eldred, M., Kane, T., Guyon, O., Hattori, M., Goto, M., Iye, M., Hayano, Y., Kamata, Y., Arimoto, N., Kobayashi, N., & Minowa, Y. (2004). Design of the subaru laser guide star adaptive optics module. Proceedings of SPIE - The International Society for Optical Engineering, 5490(PART 3), 1096-1104.
  More info

  Abstract: The laser guide star adaptive optics (AO) module for the Subaru Telescope will be installed at the f/13.9 IR Nasmyth focus, and provides the compensated image for the science instrument without change of the focal ratio. The optical components are mounted on an optical bench, and the flexure depending on the telescope pointing is eliminated. The transferred field of view for the science instrument is 2 arcmin diameter, but a 2.7 arcmin diameter field is available for tip-tilt sensing. The science path of the AO module contains five mirrors, including a pair of off-axis parabolic mirrors and a deformable mirror. It has also three additional mirrors for an image rotator. The AO module has a visible 188-element curvature based wavefront sensor (WFS) with photon-counting avalanche photodiode (APD) modules. It measures high-order terms of wavefront using either of a single laser (LGS) or natural guide star (NGS) within a 2 arcmin diameter field. The AO module has also a visible 2 × 2 sub-aperture Shack-Hartmann WFS with 16 APD modules. It measures tip-tilt and slow defocus terms of wavefront by using a single NGS within a 2.7 arcmin diameter field when a LGS is used for high-order wavefront sensing. The module has also an infrared 2 × 2 sub-aperture Shack-Hartmann WFS with a HgCdTe array as an option. Both high- and low-order visible WFSs have their own guide star acquisition units with two steering fold mirrors. The AO module has also a source simulator. It simulates LGS and NGS beams, simultaneously, with and without atmospheric turbulence by two turbulent layer at about 0 and 6 km altitudes, and reproduces the isoplanatism and the cone effect for the LGS beam.
• Guyon, O. (2003). Phase-induced amplitude apodization of telescope pupils for extrasolar terrestrial planet imaging. Astronomy and Astrophysics, 404(1), 379-387.
  More info

  Abstract: In this paper, an alternative to classical pupil apodization techniques (use of an amplitude pupil mask) is proposed. It is shown that an achromatic apodized pupil suitable for imaging of extrasolar planets can be obtained by reflection of an unapodized flat wavefront on two mirrors. By carefully choosing the shape of these two mirrors, it is possible to obtain a contrast better than 109 at a distance smaller than 2λ/d from the optical axis. Because this technique preserves both the angular resolution and light gathering capabilities of the unapodized pupil, it allows efficient detection of terrestrial extrasolar planets with a 1.5 m telescope in the visible.
• Guyon, O. (2003). Phase-induced amplitude apodization of telescope pupils for extrasolar terrestrial planet imaging. \aap, 404, 379-387.
• Guyon, O., Ridgway, S., & Otsubo, M. (2003). Phase-induced pupil apodization: A new concept for a simplier Darwin/TPF. European Space Agency, (Special Publication) ESA SP, 435-440.
  More info

  Abstract: The main obstacle toward direct imaging of exoplanets with high quality optics in space is the diffraction produced by the edges of the telescope pupil. One suggested solution to this problem is to apodize the telescope pupil with a transmissive mask. Unfortunately, this mask reduces the telescope throughput and angular resolution. In this paper, we suggest to produce an apodized pupil by geometrically remapping the entrance pupil thanks to reflective optics. We demonstrate that this technique allows direct imaging of a Earth-Sun system at 10pc in the visible in less than 1h exposure time with a 1.5m telescope.
• Guyon, O. (2002). A wide field nulling imager for TPF: The Boeing-SVS hypertelescope concept. Proceedings of SPIE - The International Society for Optical Engineering, 4852(1), 423-430.
  More info

  Abstract: The NRLA design successfully integrates an efficient nulling coronagraph in a wide-field imaging interferometer. Its imaging capabilities make it suitable for a wide range of scientific programs: planet detection and characterization as well as imaging of faint extragalactic sources. It was shown through performance study with an efficient use of the incoming photons that its sensitivity for planet detection was very good.
• Guyon, O. (2002). Field of view of fiber interferometers and applications to OHANA. Proceedings of SPIE - The International Society for Optical Engineering, 4838(2), 1440-1450.
  More info

  Abstract: The use of single-mode optical fibers in interferometers allows both easy transport of the telescope beams and very accurate visibility measurements, thanks to their spatial filtering property. Unfortunately, spatial filtering reduces the field of view coupled in the interferometer to approximately the size of the diffraction limit of the largest telescope in the array. More seriously, the time-variable wavefront aberrations induced by the atmosphere continuously change the coupling properties of the fibers, and consequently, what each arm of the interferometer "sees" on the sky. These field of view effects are especially important for the next generation of interferometers, such as OHANA (Optical Hawaiian Array for Nanoradian Astronomy), where adaptive optics makes it possible to use large individual telescopes, and the increased sensitivity makes possible the observation of fainter, more extended objects with complex morphology. In this paper, the impact of these effects is studied for observations of a variety of sources by OHANA. It is shown that the errors in visibility measurements can be reduced by signal processing techniques. Possible solutions to extend the accessible field of view of fiber-based interferometers are also presented.
• Guyon, O. (2002). Wide field interferometric imaging with single-mode fibers. Astronomy and Astrophysics, 387(1), 366-378.
  More info

  Abstract: Classical single-mode fiber interferometers, using one fiber per aperture, have very limited imaging capabilities and small field of view. Observations of extended sources (resolved by one aperture) cannot be fully corrected for wavefront aberrations: accurate measurements of object visibilities are then made very difficult from ground-based fiber interferometers. These limitations are very severe for the new generation of interferometers, which make use of large telescopes equipped with adaptive optics, but can be overcome by using several fibers per aperture. This technique improves the wide field imaging capabilities of both ground-based and space interferometers.
• Guyon, O. (2002). Wide field interferometric imaging with single-mode fibers. \aap, 387, 366-378.
• Guyon, O., & Roddier, F. (2002). A nulling wide field imager for exoplanets detection and general astrophysics. \aap, 391, 379-395.
• Guyon, O., & Roddier, F. (2002). A nulling wide field imager for exoplanets detection and general astrophysis. Astronomy and Astrophysics, 391(1), 379-395.
  More info

  Abstract: We present a solution to obtain a high-resolution image of a wide with the central source removed by destructive interference. The wide-field image is created by aperture synthesis with a rotating sparse array of telescopes in space. Nulling of the central source is achieved using a phase-mask coronagraph. The full (u, v) plane coverage delivered by the 60 m, six 3-meter telescope array is particularly well-suited for the detection and characterization of exoplanets in the infrared (DARWIN and Terrestrial Planet Finder (TPF) missions) as well as for other generic science observations. Detection (S/N = 10) of an Earth-like planet is achieved in 10 hours with a 1 μm bandwidth at 10 μm.
• Lai, O., Ridgway, S., Berger, J., Dougados, C., Coudé, V., Guyon, O., Lachaume, R., Magnier, E., Malbet, F., Ménard, F., Mourard, D., Perrin, G., Sol, H., Warren, S., & Woillez, J. (2002). OHANA: Representative science objectives. Proceedings of SPIE - The International Society for Optical Engineering, 4838(2), 1410-1423.
  More info

  Abstract: In this poster, we examine the science potential of an 800 meter interferometer such as the OHANA Array. The working assumptions are a K=12 limiting magnitude, a 0.5 milliarcsecond resolution at K band, and a small (diffraction limit of individual telescope) field of view. The science cases described herein are by no means exhaustive and perhaps not even the ones that will eventually be carried out, but serve to illustrate the potential of the array. We expect that operation of the array will be proposal driven, so the actual science will come from the Mauna Kea communities. Our philosophy is that any measurement that can be made at a dedicated interferometer facility should not be a strong driver for OHANA. Therefore the science areas discussed in the poster focus on very high angular resolution measurements of faint sources. In some cases, science which can be addressed with simpler or dedicated facilities at an exploratory level can be carried to a significant new capability with OHANA. A limiting magnitude of 12 was obtained by simple computations, but first tests on the sky with the injection module (See adjacent poster on Phase I) will help narrow down this figure. At such sensitivity, Cepheid pulsations can be studied in considerable detail for a wide range of stellar parameters, leading to enhanced confidence in the accuracy of their use for distance measurement with minimal extrapolation or inferrence. The disk/star interaction zone in young stellar objects can be resolved with unprecedented detail for a range of masses and ages, providing direct information about the jet formation region, accretion rates and disk conditions. The broad line region of active galactic nuclei can be studied in a large number of sources of differing characteristics, testing specific models for AGN nuclear structure. For OHANA Phase III, a dual-star phase tracking capability is planned. With the resulting increased sensitivity, direct brown dwarf diameter measurement will provide a strong check on evolution models. Microlensing events could be resolved and provide unique new information about the lensing and the lensed objects.
• Perrin, G., Lai, O., Woillez, J., Guerin, J., Reynaud, F., Ridgway, S. T., Léna, P., Wizinowich, P. L., Tokunaga, A. T., Nishikawa, J., Rigaut, F. J., Adamson, A. J., & Guyon, O. (2002). 'OHANA phase II: A prototype demonstrator of fiber linked interferometry between very large telescopes. Proceedings of SPIE - The International Society for Optical Engineering, 4838(2), 1290-1295.
  More info

  Abstract: The 'OHANA (Optical Hawaiian Array for Nanoradian Astronomy, means « family » in Hawaiian) aims at making a large and sensitive optical/IR array with the Mauna Kea 3 to 10 meter telescopes. Telescopes will be linked with single-mode fibers to carry the coherence of the beams from the output of the telescopes adaptive optics systems to the beam combination units. The project has been divided into three phases. The first phase is dedicated to the injection of light into single-mode fibers and to the building of the injection module. The third phase is the realization of the complete array and its use by a wide community of astronomers. In the second phase, a prototype 'OHANA will be built and the « shortest » baselines will be explored. The baselines will be located in the South-East and West parts of the observatory. An extra baseline will possibly link the two groups of telescopes if infrastructure comply with it. This phase II 'OHANA will already be the longest and most sensitive optical/IR interferometer built. Scientific targets will span young stellar objects, extragalactic sources and other types of astronomical topics which require both high angular resolution and sensitivity. This paper reviews the main characteristics of the phase II interferometer.
• Potter, D., Mart{\'\in}, E., Cushing, M., Baudoz, P., Brandner, W., Guyon, O., & Neuh{\"auser}, R. (2002). Hokupa'a-Gemini Discovery of Two Ultracool Companions to the Young Star HD 130948. \apjl, 567(2), L133-L136.
• Potter, D., Martín, E., Cushing, M. C., Baudoz, P., Brandner, W., Guyon, O., & Neuhäuser, R. (2002). Hokupa'a-gemini discovery of two ultracool companions to the young star HD 130948. Astrophysical Journal Letters, 567(2 II), L133-L136.
  More info

  Abstract: We report the discovery of two faint ultracool companions to the nearby (d ∼ 17.9 pc) young G2 V star HD 130948 (HR 5534, HIP 72567) using the Hokupa'a adaptive optics (AO) instrument mounted on the Gemini North 8 m telescope. Both objects have the same common proper motion as the primary star as seen over a 7 month baseline and have near-IR photometric colors that are consistent with an early L classification. Near-IR spectra taken with the NIRSPEC AO instrument on the Keck II telescope reveal K I lines, FeH, and H 2O band heads. Based on these spectra, we determine that both objects have a spectral type of dL2 with an uncertainty of two spectral subclasses. The position of the new companions on the H-R diagram in comparison with theoretical models is consistent with the young age of the primary star (
• Woillez, J., Sol, H., Lai, O., Guyon, O., & Perrin, G. (2002). Extragalactic astronomy with the OHANA array. Proceedings of SPIE - The International Society for Optical Engineering, 4838(2), 1389-1395.
  More info

  Abstract: The Optical Hawaiian Array for Nanoradian Astronomy (OHANA) will allow resolutions on the order of a fraction of a milliarcsecond in the near infrared. This corresponds to the suspected size of the Broad Line Region and might even allow to study the structure of the base of jets. Preliminary studies with baselines on the order of or greater than 200 meters will be needed to understand these complex objects and successively refine existing models. The continuum visibilities will distinguish any unresolved source from resolved ones. Spectrally resolved visibilities in the H band and in Paschen lines will directly test competing models for the velocity structures that produce the observed line broadening. According to the unified model, the results of these measurements may be expected to depend on the relative viewing geometry. In Phase II, OHANA will be able to select, from many dozens of candidate sources, those most likely to present distinctive differences. A preparatory survey with adaptive optics is already under way. Four different scientific cases involving the OHANA array are reviewed: Active Galactic Nuclei geometries, Broad Line Region tomography, Broad Line Region dynamics, absolute distance measurements with Active Galactic Nuclei.
• Guyon, O., & Roddier, F. (2001). Aperture Rotation Synthesis: Optimization of the(u, v)-Plane Coverage for a Rotating Phased Array of Telescopes. \pasp, 113(779), 98-104.
• Guyon, O., & Roddier, F. (2001). Aperture rotation synthesis: Optimization of the (u, v)-plane coverage for a rotating phased array of telescopes. Publications of the Astronomical Society of the Pacific, 113(779), 98-104.
  More info

  Abstract: The problem of optimizing the (u, v)-plane coverage of a rotating phased array of telescopes is assessed. We search for solutions for maximum uniform (u, v)-plane coverage. Using a simulated annealing algorithm, we find the optimal configurations for rotating arrays with between four and 10 identical telescopes. With few modifications, the same algorithm can find optimal array configurations adapted to specific observations for which the optimal (u, v)-plane coverage is different. We also demonstrate that such rotation-optimized arrays are capable of recovering images of complex sources and obtaining spectroscopic information.
• Merline, W., Close, L., Siegler, N., Potter, D., Chapman, C., Dumas, C., Menard, F., Slater, D., Baker, A., Edmunds, M., Mathlin, G., Guyon, O., & Roth, K. (2001). S/2001 (617) 1. \iaucirc, 7741, 2.
• Boker, T., Allen, R. J., Rajagopal, J., & Guyon, O. (2000). Simulating instrumental phase errors for SIM. Proceedings of SPIE - The International Society for Optical Engineering, 4006, II/-.
  More info

  Abstract: The Space Interferometer Mission (SIM) has considerable capabilities for imaging of complex targets with the resolution of a diffraction-limited 12 m telescope. The exact performance of SIM in this regard depends-among other factors - critically on its mechanical stability. For example, structural vibrations will lead to errors in the in the delay line position and thus in the derived phase of the incoming wavefront. Depending on the time constants of such vibrations and on whether or not they are random in nature, image reconstruction can be affected in different ways. In order to estimate the impact of such instrumental imperfections, we have improved our simulation code SIMSIM in a number of ways. For example, in order to develop the code further towards a possible analysis tool for real aperture synthesis data, the new version - SIMSIM-II-allows (u,v)-datapoints which are sampled on a non-regular grid. In addition, the user can choose between various models for phase and amplitude errors. Using these capabilities, we have modeled aperture synthesis observations with SIM with varying degrees of error in the visibility data. Simple metrics such as dynamic range or image fidelity are used to quantify the degradation of the reconstructed image. We demonstrate that SIMSIM-II is a suitable analysis tool for deriving hardware specifications and to optimize the stategy for imaging observations with SIM.
• Guyon, O., & Roddier, F. (2000). Direct exoplanet imaging possibilities of the nulling stellar coronagraph. Proceedings of SPIE - The International Society for Optical Engineering, 4006, I/-.
  More info

  Abstract: The nulling stellar coronagraph, first proposed by Roddier and Roddier and later demonstrated in a laboratory experiment is a technique to produce wide-field coronagraphic images. It uses a small phase-shifting mask in the focal plane to remove the central star by destructive interference. When applied to a space-based interferometric array of telescopes, it can be a powerful tool to search for faint companions around nearby stars or image circumstellar disks. A program was written to simulate the performance of a nulling stellar coronagraph for single or multi aperture telescopes in space or on the ground. In this study, we explore some aspects of the use of such a technique. By running our simulation program on various sources, we find that a nulling stellar coronagraph applied on a space interferometer like Darwin or TPF can image Earth-type planets in less than an hour of exposure time.
• Guyon, O., Roddier, C., Graves, J. E., Roddier, F., Cuevas, S., Espejo, C., Gonzalez, S., Martinez, A., Bisiacchi, G., & Vuntesmeri, V. (1999). The Nulling Stellar Coronagraph: Laboratory Tests and Performance Evaluation. \pasp, 111(764), 1321-1330.
• Guyon, O., Roddier, C., Graves, J. E., Roddier, F., Cuevas, S., Espejo, C., Gonzalez, S., Martinez, A., Bisiacchi, G., & Vuntesmeri, V. (1999). The nulling stellar coronagraph: Laboratory tests and performance evaluation. Publications of the Astronomical Society of the Pacific, 111(764), 1321-1330.
  More info

  Abstract: The nulling coronagraph, first proposed by Roddier and Roddier, uses a small mask (less than half the size of the central Airy spot) that shifts the phase of the incoming light by 180° to strongly attenuate the Airy spot as well as the rings. We report on both theoretical and laboratory performance. In our laboratory experiment, we reduce the peak intensity of the Airy pattern by a factor of 16. We derive estimates of the performance of a nulling coronagraph used on a telescope equipped with an adaptive optics system, based upon the performance of the University of Hawaii Hokupa'a adaptive optics system. On a 3.6 m telescope at 1.65 μm, it is found that a tip/tilt amplitude lower than 20 mas is needed for such a coronagraph to yield an extinction better than 2 stellar mag.
• Lachaume, R., & Guyon, O. (1999). GRB 990123. \iaucirc, 7096, 1.
• Roddier, C., Roddier, F., Graves, J., Guyon, O., Northcott, M., & Sicardy, B. (1999). Rings of Neptune. \iaucirc, 7108, 3.
• Sicardy, B., Roddier, F., Roddier, C., Perozzi, E., Graves, J. E., Guyon, O., & Northcott, M. J. (1999). Images of Neptune's ring arcs obtained by a ground-based telescope. Nature, 400(6746), 731-733.
  More info

  Abstract: Neptune has a collection of incomplete narrow rings, known as ring arcs, which should in isolation be destroyed by differential motion in a matter of months. Yet since first discovered by stellar occultations in 1984, they appear to have persisted, perhaps through a gravitational resonance effect involving the satellite Galatea. Here we report ground-based observations of the ring arcs, obtained using an adaptive optics system. Our data, and those obtained using the Hubble Space Telescope (reported in a companion paper), indicate that the ring arcs are near, but not within the resonance with Galatea, in contrast to what is predicted by some models.
• Sicardy, B., Roddier, F., Roddier, C., Perozzi, E., Graves, J., Guyon, O., & Northcott, M. (1999). Images of Neptune's ring arcs obtained by a ground-based telescope. \nat, 400(6746), 731-733.
• Roddier, C., Roddier, F., Graves, J., Guyon, O., & Northcott, M. (1998). Satellites of Neptune. \iaucirc, 6987, 2.
• Roddier, C., Roddier, F., Graves, J., Guyon, O., Northcott, M., & Sicardy, B. (1998). Satellites and Rings of Neptune. \iaucirc, 7051, 1.

Proceedings Publications

• Ahn, K., Guyon, O., Lozi, J., Vievard, S., Deo, V., Skaf, N., Belikov, R., Bos, S. P., Bottom, M., Currie, T., Frazin, R., V., G. K., Groff, T. D., Haffert, S. Y., Jovanovic, N., Kawahara, H., Kotani, T., Males, J. R., Martinache, F., , Mazin, B., et al. (2021, sep). SCExAO: a testbed for developing high-contrast imaging technologies for ELTs. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Belikov, R., Sirbu, D., Bendek, E., Pluzhnik, E., Lozi, J., Guyon, O., Ruane, G., Mejia Prada, C., Riggs, A., & Kern, B. (2021, jan). Progress in Technology Advancement of Multi-Star Wavefront Control for Exoplanet Imaging. In American Astronomical Society Meeting Abstracts, 53.
• Belikov, R., Sirbu, D., Jewell, J. B., Guyon, O., & Stark, C. C. (2021, sep). Theoretical performance limits for coronagraphs on obstructed and unobstructed apertures: how much can current designs be improved?. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Bendek, E., Noyes, M., Flores, C., Belikov, R., Sirbu, D., Mejia, P. C., Tuthill, P., & Guyon, O. (2021, jan). Status of NASA's stellar astrometry testbeds for exoplanet detection: Science and technology overview. In Space Telescopes and Instrumentation 2020: Optical, Infrared, and Millimeter Wave, 11443.
• Currie, T., & Guyon, O. (2021, mar). Ground-Based Exoplanet Direct Imaging in the Next Decade: The Path to Imaging Another Earth. In Bulletin of the American Astronomical Society, 53.
• Currie, T., Brandt, T. D., Kuzuhara, M., Chilcote, J., Cashman, E., Liu, R., Lawson, K., Tobin, T., Brandt, G. M., Guyon, O., Lozi, J., Deo, V., Vievard, S., Ahn, K., & Skaf, N. (2021, sep). A new type of exoplanet direct imaging search: a SCExAO/CHARIS survey of accelerating stars. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Currie, T., Guyon, O., Brandt, T., Chilcote, J., Lozi, J., Vievard, S., Deo, V., Lawson, K., Uyama, T., Groff, T., & Kuzuhara, M. (2021, jan). New Direct Imaging Discoveries from the Subaru Coronagraphic Extreme Adaptive Optics Project. In American Astronomical Society Meeting Abstracts, 53.
• Deo, V., Vievard, S., Cvetojevic, N., Norris, B., Guyon, O., Lozi, J., Ahn, K., Huby, E., Lacour, S., Martinache, F., Skaf, N., & Tuthill, P. (2021, sep). Wavefront sensing using non-redundant aperture masking interferometry: tests and validation on Subaru/SCExAO. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Guyon, O. (2021, jan). Synergies between ground-based and space based facilities. In 43rd COSPAR Scientific Assembly. Held 28 January - 4 February, 43.
• Guyon, O., Norris, B., Martinod, M., Ahn, K., Tuthill, P., Males, J., Wong, A., Skaf, N., Currie, T., Miller, K., Bos, S., Lozi, J., Deo, V., Vievard, S., Belikov, R., Gorkom, K., Haffert, S., Mazin, B., Bottom, M., , Frazin, R., et al. (2021, sep). High contrast imaging at the photon noise limit with self-calibrating WFS/C systems. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Haffert, S. Y., Males, J. R., Close, L., Long, J., Schatz, L., Gorkom, K., Hedglen, A., Lumbres, J., Rodack, A., Guyon, O., Knight, J., Kautz, M., & Pearce, L. (2021, sep). Data-driven subspace predictive control: lab demonstration and future outlook. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Hart, J. G., Holstein, R. G., Bos, S. P., Ruigrok, J., Snik, F., Lozi, J., Guyon, O., Kudo, T., Zhang, J., Jovanovic, N., Norris, B., Martinod, M., Groff, T. D., Chilcote, J., Currie, T., Tamura, M., Vievard, S., Sahoo, A., Deo, V., , Ahn, K., et al. (2021, aug). Full characterization of the instrumental polarization effects of the spectropolarimetric mode of SCExAO/CHARIS. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11833.
• Jensen-Clem, R., Hinz, P., Kooten, M., Fitzgerald, M. P., Sallum, S., Mazin, B., Chun, M., Max, C., Millar-Blanchaer, M., Guyon, O., Skemer, A., Stelter, R. D., & Wang, J. i. (2021, sep). The Planetary Systems Imager adaptive optics system: an initial optical design and performance analysis tool for the PSI-Red AO system. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Lallement, M., Huby, E., Lacour, S., Barjot, K., Vievard, S., Cvetojevic, N., Deo, V., Guyon, O., Kotani, T., Marchis, F., Martin, G., & Perrin, G. (2021, dec). H\textbackslashalpha imaging of protoplanets with the spectro-interferometer FIRST at the Subaru Telescope. In SF2A-2021: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics. Eds.: A. Siebert.
• Lawson, K., Currie, T., Wisniewski, J. P., Hashimoto, J., Guyon, O., Kasdin, J., Groff, T. D., Lozi, J., Brandt, T. D., Chilcote, J., Deo, V., Uyama, T., & Vievard, S. (2021, sep). High-contrast integral field spectropolarimetry of planet-forming disks with SCExAO/CHARIS. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Lawson, K., Currie, T., Wisniewski, J., Guyon, O., Lozi, J., Vievard, S., Deo, V., Brandt, T., Chilcote, J., & Uyama, T. (2021, jan). SCExAO/CHARIS High-Contrast Imaging and Integral Field Polarimetry/Spectroscopy of Planet-Forming Disks. In American Astronomical Society Meeting Abstracts, 53.
• Liberman}, J., Gee, W., Guyon, O., & Panoptes, {. (2021, jan). An Observation Portal for the PANOPTES Automated Telescope Network. In American Astronomical Society Meeting Abstracts, 53.
• Pluzhnik, E., Lozi, J., Belikov, R., Sirbu, D., Bendek, E., Guyon, O., & Fogarty, K. (2021, sep). Multi-star wavefront control with SCExAO instrument: demonstration with an internal source. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Roberge, A., Fischer, D., Peterson, B., Bean, J., Calzetti, D., Dawson, R., Dressing, C., Feinberg, L., France, K., Guyon, O., Harris, W., Marley, M., Meadows, V., Moustakas, L., O'Meara, J., Pascucci, I., Postman, M., Pueyo, L., Redding, D., , Rigby, J., et al. (2021, may). The Large UV / Optical / Infrared Surveyor (LUVOIR) Telling the Story of Life in the Universe. In Bulletin of the American Astronomical Society, 53.
• Sirbu, D., Marx, D., Belikov, R., Bendek, E., Fogarty, K. W., Kern, B., Guyon, O., Pluzhnyk, E. E., & Wilson, D. W. (2021, sep). Model validation of phase-induced amplitude apodization complex mask coronagraph for LUVOIR-A in vacuum. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Vievard, S., Ahn, K., Arriola, A., Barjot, K., Cvetojevic, N., Deo, V., Gretzinger, T., Gross, S., Guyon, O., Huby, E., Jovanovic, N., Kotani, T., Lacour, S., Lagadec, T., Lallement, M., Lapeyrere, V., Lozi, J., Marchis, F., Martin, G., , Martinod, M. -., et al. (2021, sep). Very high resolution spectro-interferometry with wavefront sensing capabilities on Subaru/SCExAO using photonics. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Wagner, K., Ertel, S., Stone, J., Leisenring, J., Apai, D., Kasper, M., Absil, O., Close, L., Defr{\`ere}, D., Guyon, O., & Males, J. (2021, sep). Imaging low-mass planets within the habitable zones of nearby stars with ground-based mid-infrared imaging. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11823.
• Anagnos, T., Maier, P., Hottinger, P., Betters, C. H., Feger, T., Leon-Saval, S. G., Gris-S{\'anchez}, I., Yerolatsitis, S., Lozi, J., Birks, T. A., Vievard, S., Jovanovic, N., Rains, A. D., Ireland, M. J., Harris, R. J., Kuo, T., Guyon, O., Norris, B., Haffert, S. Y., , Blaicher, M., et al. (2020, dec). An innovative integral field unit upgrade with 3D-printed micro-lenses for the RHEA at Subaru. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11451.
• Barjot, K., Huby, E., Vievard, S., Cvetojevic, N., Lacour, S., Martin, G., Deo, V., Lapeyrere, V., Rouan, D., Guyon, O., Lozi, J., Jovanovic, N., Cassagnettes, C., Perrin, G., Marchis, F., Duch{\^ene}, G., & Kotani, T. (2020, dec). Laboratory characterization of FIRSTv2 photonic chip for the study of substellar companions. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11446.
• Barjot, K., Martinez, P., Beaulieu, M., Gouvret, C., Marcotto, A., Guyon, O., Belhadi, M., Caillat, A., Behaghel, T., Le, D. J., Dohlen, K., & Vigan, A. (2020, dec). A metrological characterization of the SPEED test-bed PIAACMC components. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11451.
• Close}, L. M., Males, J., Long, J. D., Van, G. K., Hedglen, A. D., Kautz, M., Lumbres, J., Haffert, S. Y., Follette, K., Wagner, K., Miller, K., Apai, D., Wu, Y., Guyon, O., Schatz, L., Rodack, A., Doelman, D., Snik, F., Knight, J. M., , Morzinski, K., et al. (2020, dec). Prediction of the planet yield of the MaxProtoPlanetS high-contrast survey for H-alpha protoplanets with MagAO-X based on first light contrasts. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Cook, T., Jovanovic, N., Gee, W., Notaro, G., Mukherjea, A., Ganesh, M., Boucher, L., Ruane, G., Guyon, O., Synge, J., Guyon, K., & Mawet, D. (2020, jan). Detecting transiting exoplanets with a low-cost robotic telescope system. In American Astronomical Society Meeting Abstracts \#235, 235.
• Currie, T., Guyon, O., Lozi, J., Sahoo, A., Vievard, S., Deo, V., Chilcote, J., Groff, T., Brandt, T. D., Lawson, K., Skaf, N., Martinache, F., & Kasdin, N. J. (2020, dec). On-sky performance and recent results from the Subaru coronagraphic extreme adaptive optics system. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Currie, T., Kudo, T., Muto, T., Lyra, W., Dong, R., Guyon, O., Lozi, J., Wagner, K., Brandt, T., Chilcote, J., Hashimoto, J., & Tamura, M. (2020, jun). SCExAO/CHARIS Imaging of a Candidate Protoplanet/Planet-Induced Structure Around a Young Star. In American Astronomical Society Meeting Abstracts \#236, 236.
• Currie, T., Pluzhnik, E., Belikov, R., Miller, K., Guyon, O., & Males, J. (2020, jan). Developing and Demonstrating Linear Dark Field Control for Exo-Earth Imaging with the Ames Coronagraph Experiment Testbed. In American Astronomical Society Meeting Abstracts \#235, 235.
• Ferreira, F., Sevin, A., Bernard, J., Guyon, O., Bertrou-Cantou, A. .., Raffard, J., Vidal, F., Gendron, E., & Gratadour, D. (2020, dec). Hard real-time core software of the AO RTC COSMIC platform: architecture and performance. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Gee}, W., Walawender, J., Guyon, O., Schwab, C., & Panoptes, {. (2020, jan). Project PANOPTES: Efficiency and Yield of a Low-Cost Transiting Exoplanet Survey using DSLR Cameras. In American Astronomical Society Meeting Abstracts \#235, 235.
• Guyon, O., Belikov, R., Bendek, E., Bos, S., Currie, T., Groff, T., Laugier, R., Lozi, J., Males, J., Martinache, F., Mazin, B., Miller, K., Norris, B., Sahoo, A., & Vievard, S. (2020, jan). Wavefront Sensing and Control R\&D on the SCExAO Testbed. In American Astronomical Society Meeting Abstracts \#235, 235.
• Guyon, O., Lozi, J., Vievard, S., Belikov, R., Bendek, E., Bos, S., Currie, T., Deo, V., Fitzgerald, M., Gratadour, D., Groff, T., Jovanovic, N., Kawahara, H., Kotani, T., Kudo, T., Lopez, C., Ltaief, H., Males, J., Martinache, F., , Martinod, M., et al. (2020, dec). Validating advanced wavefront control techniques on the SCExAO testbed/instrument. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Guyon, O., Sevin, A., Ferreira, F., Ltaief, H., Males, J., Deo, V., Gratadour, D., Cetre, S., Martinache, F., Lozi, J., Vievard, S., Fruitwala, N., Bos, S., & Skaf, N. (2020, dec). Adaptive optics real-time control with the compute and control for adaptive optics (Cacao) software framework. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Hagelberg, J., Restori, N., Wildi, F., Chazelas, B., Baranec, C., Guyon, O., Genolet, L., Sordet, M., & Riddle, R. (2020, dec). KalAO the swift adaptive optics imager on the 1.2m Euler Swiss telescope in La Silla, Chile. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Holstein, R. G., Bos, S. P., Ruigrok, J., Lozi, J., Guyon, O., Norris, B., Snik, F., Chilcote, J., Currie, T., Groff, T. D., Hart, J., Jovanovic, N., Kasdin, J., Kudo, T., Martinache, F., Mazin, B., Sahoo, A., Tamura, M., Vievard, S., , Walter, A., et al. (2020, dec). Calibration of the instrumental polarization effects of SCExAO-CHARIS' spectropolarimetric mode. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11447.
• Kotani, T., Kawahara, H., Ishizuka, M., Jovanovic, N., Vievard, S., Lozi, J., Sahoo, A., Guyon, O., Yoneta, K., & Tamura, M. (2020, dec). Extremely high-contrast, high spectral resolution spectrometer REACH for the Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Krishnamoorthy, P., Boucher, L., Cook, T., Gee, W., Guyon, K., Guyon, O., Jovanovic, N., Synge, J., & Walawender, J. (2020, jun). Project PANOPTES \textemdash A network of automated robotic telescopes built by citizen scientists to detect transiting exoplanets.. In American Astronomical Society Meeting Abstracts \#236, 236.
• Krishnamoorthy, P., Walawender, J., Gee, W. T., & Guyon, O. (2020, dec). PANOPTES: A citizen science project to discover exoplanets from your backyard using off-the-shelf hardware. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11445.
• Lozi, J., Guyon, O., Jovanovic, N., Norris, B., Groff, T., Chilcote, J., Kasdin, N., Kudo, T., Tamura, M., Zhang, J., Bos, S., Snik, F., Doelman, D., Vievard, S., Sahoo, A., Currie, T., & Martinache, F. (2020, jan). New NIR spectro-polarimetric modes for the SCExAO instrument. In American Astronomical Society Meeting Abstracts \#235, 235.
• Lozi, J., Guyon, O., Kudo, T., Zhang, J., Jovanovic, N., Norris, B., Martinod, M., Groff, T. D., Chilcote, J., Tamura, M., Bos, S., Snik, F., Vievard, S., Sahoo, A., Deo, V., Martinache, F., & Kasdin, J. (2020, dec). New NIR spectro-polarimetric modes for the SCExAO instrument. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Lozi, J., Guyon, O., Vievard, S., Sahoo, A., Deo, V., Jovanovic, N., Norris, B., Martinod, M., Mazin, B., Walter, A., Fruitwala, N., Steiger, S., Davis, K., Tuthill, P., Kudo, T., Kawahara, H., Kotani, T., Ireland, M., Anagnos, T., , Schwab, C., et al. (2020, dec). Status of the SCExAO instrument: recent technology upgrades and path to a system-level demonstrator for PSI. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Males, J. R., Close, L. M., Guyon, O., Hedglen, A. D., Van, G. K., Long, J. D., Kautz, M., Lumbres, J., Schatz, L., Rodack, A., Miller, K., Doelman, D., Snik, F., Bos, S., Knight, J. M., Morzinski, K., Gasho, V., Keller, C., Haffert, S., & Pearce, L. (2020, dec). MagAO-X first light. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Marafatto, L., Bergomi, M., Biondi, F., Carolo, E., De, P. M., Greggio, D., Lessio, L., Mesa, D., Radhakrishnan, S., Umbriaco, G., Vassallo, D., Viotto, V., Bianco, A., Dima, M., D'Orazi, V., Grenz, P., Leisenring, J. M., Mohr, L., Montoya, M., , Zanutta, A., et al. (2020, dec). SHARK-NIR, toward the installation at the Large Binocular Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Nishikawa, J., Murakami, N., Lozi, J., Guyon, O., Habu, K., Ichien, H., Yoneta, K., Sudoh, S., Kumaki, K., Kumagai, S., Jovanovic, N., & Martinache, F. (2020, dec). Combination of apodized pupil and phase mask coronagraph for SCExAO at Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11447.
• Norris, B. R., Tuthill, P., Jovanovic, N., Lozi, J., Guyon, O., Cvetojevic, N., & Martinache, F. (2020, jan). Diffraction-limited polarimetric imaging of protoplanetary disks and mass-loss shells with VAMPIRES. In Advances in Optical Astronomical Instrumentation 2019, 11203.
• Okita, H., Terai, T., Guyon, O., Takato, N., & Takami, H. (2020, dec). Effect of the lack of the windscreen at Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11445.
• Ono, Y. H., Minowa, Y., Guyon, O., Clergeon, C. S., Mieda, E., Lozi, J., Hattori, T., & Akiyama, M. (2020, dec). Overview of AO activities at Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Sahoo, A., Lozi, J., Vievard, S., Guyon, O., Kotani, T., Kawahara, H., Jovanovic, N., Deo, V., & Ishizuka, M. (2020, dec). Constraining orbits and masses of stellar companions with SCExAO imaging and REACH spectroscopy. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Tobin, T. L., Chilcote, J., Brandt, T., Currie, T., Groff, T., Lozi, J., & Guyon, O. (2020, dec). The automated data extraction, processing, and tracking system for CHARIS. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11452.
• Uyama, T., Currie, T., De Rosa, R., Brandt, T., Hori, Y., Mede, K., Guyon, O., Lozi, J., & Tamura, M. (2020, jan). Characterization of kappa And b with SCExAO. In American Astronomical Society Meeting Abstracts \#235, 235.
• Vievard, S., Bos, S., Cassaing, F., Currie, T., Deo, V., Guyon, O., Jovanovic, N., Keller, C., Lamb, M., Lopez, C., Lozi, J., Martinache, F., Miller, K., Montmerle-Bonnefois, A. .., Mugnier, L., N'Diaye, M., Norris, B., Sahoo, A., Sauvage, J. -., , Skaf, N., et al. (2020, dec). Focal plane wavefront sensing on SUBARU/SCExAO. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11448.
• Vievard, S., Huby, E., Lacour, S., Barjot, K., Martin, G., Cvetojevic, N., Deo, V., Guyon, O., Lozi, J., Kotani, T., Jovanovic, N., Marchis, F., Duch{\^ene}, G., Lapeyrere, V., Rouan, D., & Perrin, G. (2020, dec). FIRST, a pupil-remapping fiber interferometer at the Subaru Telescope: on-sky results. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11446.
• Wang, J. J., Wallace, J., Jovanovic, N., Guyon, O., Roberts, M., & Mawet, D. (2020, dec). An atmospheric dispersion corrector design with milliarcsecond-level precision from 1 to 4 microns for high dispersion coronagraphy. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11447.
• Belikov, R., Barclay, T., Batalha, N. M., Bendek, E., Chakrabarti, S., Currie, T., Goldblatt, C., Guyon, O., Kasdin, N. J., Kasting, J., Kern, B. D., Lissauer, J. J., Lozi, J., Males, J. R., Marchis, F., Marley, M. S., Marois, C., McElwain, M. W., Mendillo, C. B., , Morse, J. A., et al. (2019, sep). Imaging Earth-like Exoplanets with a Small Space Telescope. In Bulletin of the American Astronomical Society, 51.
• Belikov, R., Barclay, T., Batalha, N. M., Bendek, E., Chakrabarti, S., Currie, T., Goldblatt, C., Guyon, O., Kasdin, N. J., Kasting, J., Kern, B. D., Lissauer, J. J., Lozi, J., Males, J. R., Marchis, F., Marley, M. S., Marois, C., McElwain, M. W., Mendillo, C. B., , Morse, J. A., et al. (2019, sep). Imaging Earth-like Exoplanets with a Small Space Telescope. In baas, 51.
• Belikov, R., Sirbu, D., Bendek, E., Jewell, J. B., Shaklan, S., & Guyon, O. (2019, jan). Theoretical Limits for Exoplanet Detection with Coronagraphs on Obstructed Apertures. In American Astronomical Society Meeting Abstracts #233, 233.
• Bendek, E., Sirbu, D., Belikov, R., Lozi, J., Guyon, O., Pluzhnik, E., & Currie, T. (2019, sep). Demonstration of multi-star wavefront control using SCExAO. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11117.
• Chilcote, J., Groff, T., Kasdin, N., {Brand, t. T., Guyon, O., Currie, T., Lozi, J., Rizzo, M., Jovanovic, N., Takato, N., Hayashi, M., Goebel, S., Marois, C., Gerard, B., Rich, E. A., Asensio-Torres, R., & Kwon, J. (2019, jan). The CHARIS Integral Field Spectrograph with SCExAO. In American Astronomical Society Meeting Abstracts #233, 233.
• Currie, T., Guyon, O., Kasdin, N., {Brand, t. T., Groff, T., Lozi, J., Chilcote, J., Uyama, T., Nielsen, E., Blunt, S., Marois, C., Jovanovic, N., Kuzuhara, M., & Tamura, M. (2019, jan). Direct Imaging and Spectral Characterization of Extrasolar Planets with the SCExAO/CHARIS. In American Astronomical Society Meeting Abstracts #233, 233.
• Currie, T., Guyon, O., Lozi, J., Groff, T., Kasdin, N. J., Martinache, F., Brandt, T. D., Chilcote, J., Marois, C., Gerard, B., Jovanovic, N., & Vievard, S. (2019, sep). Performance and early science with the Subaru Coronagraphic Extreme Adaptive Optics project. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11117.
• Currie, T., Pluzhnik, E., Belikov, R., & Guyon, O. (2019, sep). Developing linear dark-field control for exoplanet direct imaging in the laboratory and on ground-based telescopes. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11117.
• Fitzgerald, M., Bailey, V., Baranec, C., Batalha, N., Benneke, B., Beichman, C., Brandt, T., Chilcote, J., Chun, M., Crossfield, I., Currie, T., Davis, K., Dekany, R., Delorme, J., Dong, R., Doyon, R., Dressing, C., Echeverri, D., Fortney, J., , Frazin, R. A., et al. (2019, sep). The Planetary Systems Imager for TMT. In Bulletin of the American Astronomical Society, 51.
• Fitzgerald, M., Bailey, V., Baranec, C., Batalha, N., Benneke, B., Beichman, C., Brandt, T., Chilcote, J., Chun, M., Crossfield, I., Currie, T., Davis, K., Dekany, R., Delorme, J., Dong, R., Doyon, R., Dressing, C., Echeverri, D., Fortney, J., , Frazin, R. A., et al. (2019, sep). The Planetary Systems Imager for TMT. In baas, 51.
• Gee, W. T., Guyon, O., Schwab, C., Walawender, J., Zellem, R. T., Jovanovic, N., & Coutts, D. (2019, jan). Project PANOPTES: A Unique Approach for Exoplanet Transit Detection using DSLR Cameras. In American Astronomical Society Meeting Abstracts #233, 233.
• Gerard, B., Marois, C., Currie, T., Groff, T., Guyon, O., Jovanovic, N., & Lozi, J. (2019, jan). Observing Two-Component Debris Disks with SCExAO+CHARIS. In American Astronomical Society Meeting Abstracts #233, 233.
• Guyon, O., Bottom, M., Chun, M., Close, L., Davis, K., Fitzgerald, M. P., Frazin, R., Hinz, P., Jensen-Clem, R., Jovanovic, N., Kawahara, H., Konopacky, Q., Lozi, J., Males, J., Marois, C., Mawet, D., Mazin, B., Narita, N., Ruane, G., , Sallum, S., et al. (2019, sep). A Technology Validation Program for near-IR Habitable Exoplanet Imaging with GMT and TMT. In Bulletin of the American Astronomical Society, 51.
• Guyon, O., Bottom, M., Chun, M., Close, L., Davis, K., Fitzgerald, M. P., Frazin, R., Hinz, P., Jensen-Clem, R., Jovanovic, N., Kawahara, H., Konopacky, Q., Lozi, J., Males, J., Marois, C., Mawet, D., Mazin, B., Narita, N., Ruane, G., , Sallum, S., et al. (2019, sep). A Technology Validation Program for near-IR Habitable Exoplanet Imaging with GMT and TMT. In baas, 51.
• Guyon, O., Lozi, J., Vievard, S., Sahoo, A., Jovanovic, N., Currie, T., Pathak, P., Martinache, F., Kudo, T., Tamura, M., Singh, G., Clergeon, C., Minowa, Y., Ono, Y., Mieda, E., Mazin, B., Walter, A., Cvetojevic, N., Lacour, S., , Huby, E., et al. (2019, jan). The SCExAO High Contrast Imaging Platform: Current and Upcoming Capabilities. In American Astronomical Society Meeting Abstracts \#233, 233.
• Jovanovic, N., Beichman, C., Blake, C., Bottom, M., Chilcote, J., Coker, C., Crass, J., Crepp, J. R., Cvetojevic, N., Daal, M., Dagenais, M., Davis, K., Dekany, R., Figer, D., Fitzgerald, M. P., Gatkine, P., Guyon, O., Halverson, S., Harris, R. J., , Hinz, P. M., et al. (2019, sep). Enabling the next generation of scientific discoveries by embracing photonic technologies. In Bulletin of the American Astronomical Society, 51.
• Jovanovic, N., Beichman, C., Blake, C., Bottom, M., Chilcote, J., Coker, C., Crass, J., Crepp, J. R., Cvetojevic, N., Daal, M., Dagenais, M., Davis, K., Dekany, R., Figer, D., Fitzgerald, M. P., Gatkine, P., Guyon, O., Halverson, S., Harris, R. J., , Hinz, P. M., et al. (2019, sep). Enabling the next generation of scientific discoveries by embracing photonic technologies. In baas, 51.
• Lipartito, I., Mazin, B. A., Walter, A. B., Bockstiegel, C., Fruitwala, N., Meeker, S., Szypryt, P., Zobrist, N., Coiffard, G., Steiger, S., Swimmer, N., Smith, J., Bailey, J. I., Davis, K., Dodkins, H. R., Guyon, O., Jovanovic, N., Lozi, J., Sahoo, A., , Vievard, S., et al. (2019, aug). Optical/Near-IR Microwave Kinetic Inductance Detector-based Integral Field Spectrographs for High-Contrast Observations. In AAS/Division for Extreme Solar Systems Abstracts, 51.
• Males, J., Close, L. M., Guyon, O., Sitarski, B., Bouchez, A., Weinberger, A., & Fitzgerald, M. P. (2019, sep). GMagAO-X: extreme adaptive optics & coronagraphy for GMT at first light. In baas, 51.
• Males, J., Close, L. M., Guyon, O., Sitarski, B., Bouchez, A., Weinberger, A., & Fitzgerald, M. P. (2019, sep). GMagAO-X: extreme adaptive optics \& coronagraphy for GMT at first light. In Bulletin of the American Astronomical Society, 51.
• Mazoyer, J., Baudoz, P., Belikov, R., Crill, B., Fogarty, K., Galicher, R., Groff, T., Guyon, O., Juanola-Parramon, R., Kasdin, J., Leboulleux, L., Sayson, J. L., Mawet, D., Prada, C. M., Mennesson, B., N'Diaye, M., Perrin, M., Pueyo, L., Roberge, A., , Ruane, G., et al. (2019, sep). High-Contrast Testbeds for Future Space-Based Direct Imaging Exoplanet Missions. In Bulletin of the American Astronomical Society, 51.
• Mazoyer, J., Baudoz, P., Belikov, R., Crill, B., Fogarty, K., Galicher, R., Groff, T., Guyon, O., Juanola-Parramon, R., Kasdin, J., Leboulleux, L., Sayson, J. L., Mawet, D., Prada, C. M., Mennesson, B., N'Diaye, M., Perrin, M., Pueyo, L., Roberge, A., , Ruane, G., et al. (2019, sep). High-Contrast Testbeds for Future Space-Based Direct Imaging Exoplanet Missions. In baas, 51.
• Mukherjea, A., Ganesh, M., Jovanovic, N., Gee, W., Synge, J., Boucher, L., Guyon, O., Guyon, K., Ruane, G., & Mawet, D. (2019, jan). Project PANOPTES: Transiting Exoplanet Detection using Low-Cost Robotic Telescopes. In American Astronomical Society Meeting Abstracts #233, 233.
• Pueyo, L., Bailey, V., Bolcar, M., Coyle, L., Feinberg, L., Groff, T., Guyon, O., Jewell, J., Kasdin, J., Knight, S., Mawet, D., Mazoyer, J., Mennesson, B., Perrin, M., Redding, D., Riggs, A. J., Ruane, G., Soummer, R., Stark, C., , Will, S., et al. (2019, sep). Wavefront Sensing and Control technologies for Exo-Earth imaging. In Bulletin of the American Astronomical Society, 51.
• Pueyo, L., Bailey, V., Bolcar, M., Coyle, L., Feinberg, L., Groff, T., Guyon, O., Jewell, J., Kasdin, J., Knight, S., Mawet, D., Mazoyer, J., Mennesson, B., Perrin, M., Redding, D., Riggs, A. J., Ruane, G., Soummer, R., Stark, C., , Will, S., et al. (2019, sep). Wavefront Sensing and Control technologies for Exo-Earth imaging. In baas, 51.
• Uyama, T., Norris, B., Guyon, O., & Tamura, M. (2019, aug). Search for Hensuremath{alpha} from accreting protoplanets with Subaru/SCExAO+VAMPIRES. In AAS/Division for Extreme Solar Systems Abstracts, 51.
• Wisniewski, J., Currie, T., Marois, C., Grady, C., Lawson, K., Guyon, O., Kasdin, N., Groff, T., Brandt, T., Chilcote, J., & Lozi, J. (2019, jan). A New Assessment of the Candidate Protoplanets Orbiting LkCa 15 Using SCExAO/CHARIS High-Contrast Direct Spectroscopy. In American Astronomical Society Meeting Abstracts #233, 233.
• Wright, S. A., Sherwood, L. B., Atreya, S., Boss, A. P., Falkowski, P., Farmer, J. D., Guyon, O., Joyce, G. F., Kasting, J. F., Meadows, V., Neches, P. M., Pilcher, C. B., Renn{'o}, N. O., Rogers, K., Schmidt, B. E., Summons, R. E., & Westall, F. (2019, jan). Astrobiology Science Strategy for the Search for Life in the Universe. In American Astronomical Society Meeting Abstracts #233, 233.
• Xin, Y., Douglas, E., Allan, G. W., Clark, J. R., Guyon, O., Lumbres, J. R., Males, J., & Cahoy, K. L. (2019, jan). Diffraction analysis of Laser Guide Star enabled cophasing wavefront control for large segmented aperture space telescopes. In American Astronomical Society Meeting Abstracts #233, 233.
• Bailey, V., Bottom, M., Cady, E., Cantalloube, F., Boer, J., Groff, T., Krist, J., Millar-Blanchaer, M., Vigan, A., Chilcote, J., Choquet, E., De, R. R., Girard, J., Guyon, O., Kern, B., Lagrange, A., Macintosh, B., Males, J., Marois, C., , Meshkat, T., et al. (2018, aug). Lessons for WFIRST CGI from ground-based high-contrast systems. In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Baranec, C., Chun, M., Hall, D., Connelley, M., Hodapp, K., Huber, D., Liu, M., Magnier, E., Meech, K., Takamiya, M., Griffiths, R., Riddle, R., Dekany, R., Kasliwal, M., Lau, R., Law, N., Guyon, O., Pater, I., Wong, M., , Ofek, E., et al. (2018, jul). The Robo-AO-2 facility for rapid visible/near-infrared AO imaging and the demonstration of hybrid techniques. In Adaptive Optics Systems VI, 10703.
• Beaulieu, M., Martinez, P., Abe, L., Guyon, O., Gouvret, C., Dejonghe, J., & Preis, O. (2018, jul). An end-to-end Fresnel propagation model for SPEED: PIAACMC implementation and performance. In Ground-based and Airborne Telescopes VII, 10700.
• Belikov, R., Bryson, S., Sirbu, D., Guyon, O., Bendek, E., & Kern, B. (2018, aug). Design and performance analysis of a PIAACMC coronagraph on a segmented aperture. In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Bendek, E., Tuthill, P., Guyon, O., Vasisht, G., Belikov, R., Larkin, K., Beichman, C., Shao, M., Mamajek, E., Sirbu, D., & Coyle, L. (2018, aug). Precision astrometry mission for exoplanet detection around binary stars. In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Bond, C., Wizinowich, P., Chun, M., Mawet, D., Lilley, S., Cetre, S., Jovanovic, N., Delorme, J., Wetherell, E., Jacobson, S., Lockhart, C., Warmbier, E., Wallace, J., Hall, D., Goebel, S., Guyon, O., Plantet, C., Agapito, G., Giordano, C., , Esposito, S., et al. (2018, jul). Adaptive optics with an infrared pyramid wavefront sensor. In Adaptive Optics Systems VI, 10703.
• Cetre, S., Guyon, O., Bond, C., Chun, M., Mawet, D., Wizinowich, P., Lockhart, C., Goebel, S., & Wetherell, E. (2018, jul). A near-infrared pyramid wavefront sensor for Keck adaptive optics: real-time controller. In Adaptive Optics Systems VI, 10703.
• Clark, J., Carlton, A., Douglas, E., Males, J., Lumbres, J., Feinberg, L., Guyon, O., Marlow, W., & Cahoy, K. (2018, jan). Capabilities of a Laser Guide Star for a Large Segmented Space Telescope. In American Astronomical Society Meeting Abstracts \#231, 231.
• Clergeon, C., Minowa, Y., Guyon, O., Ono, Y., Mieda, E., Skaf, N., Yoshida, H., Hayano, Y., Hattori, T., Schubert, K., Sahoo, A., Lozi, J., & Vievard, S. (2018, jul). Subaru AO188 upgrade phase 1: integration of the new real-time system. In Adaptive Optics Systems VI, 10703.
• Currie, T., Guyon, O., Kasdin, J., Brandt, T., Groff, T., Jovanovic, N., Lozi, J., Chilcote, J., Uyama, T., Ascensio-Torres, R. .., Tamura, M., & Norris, B. (2018, jan). Early Direct Imaging and Spectral Characterization of Extrasolar Planets with the SCExAO/CHARIS. In American Astronomical Society Meeting Abstracts \#231, 231.
• Dirnberger, M., Rigaut, F., Minowa, Y., Conan, R., Guyon, O., Gratadour, D., & Korkiakoski, V. (2018, jul). Rolling shutter detector data flow strategies to push the limits of AO performance. In Adaptive Optics Systems VI, 10703.
• Farinato, J., Agapito, G., Bacciotti, F., Baffa, C., Baruffolo, A., Bergomi, M., Bianco, A., Bongiorno, A., Carbonaro, L., Carolo, E., Carlotti, A., Chinellato, S., Close, L., De Pascale, M., Dima, M., D'Orazi, V., Esposito, S., Fantinel, D., Farisato, G., , Gaessler, W., et al. (2018, jul). SHARK-NIR: the coronagraphic camera for LBT in the AIV phase at INAF-Padova. In Adaptive Optics Systems VI, 10703.
• Fujishiro, N., Sakon, I., Enya, K., Guyon, O., Nishikawa, J., Murakami, N., Kotani, T., Tamura, M., Takahashi, A., Roellig, T., & Ennico-Smith, K. .. (2018, jul). PIAA coronagraph for Origins Space telescope (OST) mid-infrared imager, spectrometer, coronagraph (MISC) instrument. In Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III, 10706.
• Gaudi, B., Mennesson, B., Seager, S., Cahoy, K., Clarke, J., Domagal-Goldman, S. .., Feinberg, L., Guyon, O., Kasdin, J., Marois, C., Mawet, D., Tamura, M., Mouillet, D., Prusti, T., Quirrenbach, A., Robinson, T., Rogers, L., Scowen, P., Somerville, R., , Stapelfeldt, K., et al. (2018, aug). The Habitable Exoplanet Observatory (HabEx). In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Gerard, B., Marois, C., Galicher, R., Veran, J., Macintosh, B., Guyon, O., Lozi, J., Pathak, P., & Sahoo, A. (2018, jun). Fast Coherent Differential Imaging for Exoplanet Imaging. In American Astronomical Society Meeting Abstracts \#232, 232.
• Guyon, O., Mazin, B., Fitzgerald, M., Mawet, D., Marois, C., Skemer, A., Lozi, J., & Males, J. (2018, jul). Wavefront control architecture and expected performance for the TMT Planetary Systems Imager. In Adaptive Optics Systems VI, 10703.
• Guyon, O., Sevin, A., Gratadour, D., Bernard, J., Ltaief, H., Sukkari, D., Cetre, S., Skaf, N., Lozi, J., Martinache, F., Clergeon, C., Norris, B., Wong, A., & Males, J. (2018, jul). The compute and control for adaptive optics (CACAO) real-time control software package. In Adaptive Optics Systems VI, 10703.
• Hart, M., Schatz, L. H., Males, J. R., Close, L. M., Guyon, O., Durney, O. F., Lumbres, J., Miller, K., Knight, J., Rodack, A., Long, J., Van Gorkum, K., Jean, M., & Kautz, M. (2018, July). Design of the MagAO-X Pyramid Wavefront Sensor. In Adaptive Optics Systems VI, 10703.
• Jovanovic, N., Absil, O., Baudoz, P., Beaulieu, M., Bottom, M., Cady, E., Carlomagno, B., Carlotti, A., Doelman, D., Fogarty, K., Galicher, R., Guyon, O., Haffert, S., Huby, E., Jewell, J., Keller, C., Kenworthy, M., Knight, J., K{\"uhn}, J., , Miller, K., et al. (2018, jul). Review of high-contrast imaging systems for current and future ground-based and space-based telescopes: Part II. Common path wavefront sensing/control and coherent differential imaging. In Adaptive Optics Systems VI, 10703.
• Kasdin, N., Groff, T., Brandt, T., Currie, T., Rizzo, M., Chilcote, J., Guyon, O., Jovanovic, N., Lozi, J., Norris, B., & Tamura, M. (2018, jan). The CHARIS Integral Field Spectrograph with SCExAO: Data Reduction and Performance. In American Astronomical Society Meeting Abstracts \#231, 231.
• Knight, J., Guyon, O., Lozi, J., Jovanovic, N., & Males, J. (2018, jul). Phase-induced amplitude apodization complex-mask coronagraph tolerancing and analysis. In Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III, 10706.
• K{\"aufl}, H., Kasper, M., Arsenault, R., Jakob, G., Leveratto, S., Zins, G., Fuenteseca, E., Riquelme, M., Siebenmorgen, R., Sterzik, M., Ageorges, N., Gutruf, S., Kampf, D., Reutlinger, A., Absil, O., Carlomagno, B., Guyon, O., Klupar, P., Mawet, D., , Ruane, G., et al. (2018, jul). NEAR: new earths in the Alpha Cen Region (bringing VISIR as a ``visiting instrument'' to ESO-VLT-UT4). In Ground-based and Airborne Instrumentation for Astronomy VII, 10702.
• Lozi, J., Guyon, O., Jovanovic, N., Goebel, S., Pathak, P., Skaf, N., Sahoo, A., Norris, B., Martinache, F., N'Diaye, M., Mazin, B., Walter, A., Tuthill, P., Kudo, T., Kawahara, H., Kotani, T., Ireland, M., Cvetojevic, N., Huby, E., , Lacour, S., et al. (2018, jul). SCExAO, an instrument with a dual purpose: perform cutting-edge science and develop new technologies. In Adaptive Optics Systems VI, 10703.
• Lumbres, J., Males, J., Douglas, E., Close, L., Guyon, O., Cahoy, K., Carlton, A., Clark, J., Doelman, D., Feinberg, L., Knight, J., Marlow, W., Miller, K., Morzinski, K., Por, E., Rodack, A., Schatz, L., Snik, F., Van Gorkom, K., & Wilby, M. (2018, jul). Modeling coronagraphic extreme wavefront control systems for high contrast imaging in ground and space telescope missions. In Adaptive Optics Systems VI, 10703.
• Males, J., Close, L., Miller, K., Schatz, L., Doelman, D., Lumbres, J., Snik, F., Rodack, A., Knight, J., Van Gorkom, K., Long, J., Hedglen, A., Kautz, M., Jovanovic, N., Morzinski, K., Guyon, O., Douglas, E., Follette, K., Lozi, J., , Bohlman, C., et al. (2018, jul). MagAO-X: project status and first laboratory results. In Adaptive Optics Systems VI, 10703.
• Martinez, P., Beaulieu, M., Guyon, O., Abe, L., Gouvret, C., Dejonghe, J., & Preis, O. (2018, jul). Design, specification, and manufacturing of a PIAACMC for the SPEED testbed. In Ground-based and Airborne Instrumentation for Astronomy VII, 10702.
• Martinez, P., Janin-Potiron, P. .., Beaulieu, M., Gouvret, C., Dejonghe, J., Spang, A., Postnikova, M., Baudoz, P., Guyon, O., Preis, O., Abe, L., N'Diaye, M., & Marcotto, A. (2018, jul). The segmented pupil experiment for exoplanet detection: Part 3. Advances and first light with segments cophasing. In Adaptive Optics Systems VI, 10703.
• Miller, K., Males, J., Guyon, O., Close, L., Doelman, D., Snik, F., Por, E., Wilby, M., Bohlman, C., Lumbres, J., Van Gorkom, K., Kautz, M., Rodack, A., Knight, J., Jovanovic, N., Morzinski, K., & Schatz, L. (2018, jul). Focal plane wavefront sensing and control strategies for high-contrast imaging on the MagAO-X instrument. In Adaptive Optics Systems VI, 10703.
• Ono, Y., Minowa, Y., Clergeon, C., Mieda, E., Guyon, O., Lozi, J., Akiyama, M., Rigaut, F., Hayano, Y., & Oya, S. (2018, jul). On-going and future AO activities on Subaru Telescope. In Adaptive Optics Systems VI, 10703.
• Rains, A., Ireland, M., Jovanovic, N., Bento, J., Feger, T., Lozi, J., Schwab, C., Coutts, D., Guyon, O., Arriola, A., Gross, S., & Harris, J. (2018, jul). Development of the single-mode fiber integral field unit for the RHEA Spectrograph. In Ground-based and Airborne Instrumentation for Astronomy VII, 10702.
• Rodack, A., Males, J., Guyon, O., Mazin, B., Fitzgerald, M., & Mawet, D. (2018, jul). Real-time estimation and correction of quasi-static aberrations in ground-based high contrast imaging systems with high frame-rates. In Adaptive Optics Systems VI, 10703.
• Ruane, G., Riggs, A., Mazoyer, J., Por, E., N'Diaye, M., Huby, E., Baudoz, P., Galicher, R., Douglas, E., Knight, J., Carlomagno, B., Fogarty, K., Pueyo, L., Zimmerman, N., Absil, O., Beaulieu, M., Cady, E., Carlotti, A., Doelman, D., , Guyon, O., et al. (2018, aug). Review of high-contrast imaging systems for current and future ground- and space-based telescopes I: coronagraph design methods and optical performance metrics. In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Sahoo, A., Guyon, O., Clergeon, C., Skaf, N., Minowa, Y., Lozi, J., Jovanovic, N., & Martinache, F. (2018, jul). Subaru Coronagraphic Extreme-AO (SCExAO) wavefront control: current status and ongoing developments. In Adaptive Optics Systems VI, 10703.
• Sakon, I., Roellig, T., Ennico-Smith, K. .., Matsuo, T., Ikeda, Y., Yamamuro, T., Fujishiro, N., Enya, K., Takahashi, A., Wada, T., Guyon, O., Kotani, T., Nishikawa, J., Murakami, N., Sarugaku, Y., & Burgarella, D. (2018, jul). The mid-infrared imager, spectrometer, coronagraph (MISC) for the Origins Space telescope (OST). In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Sakon}, I., Roellig, T., Ennico, K., Matsuo, T., Ikeda, Y., Yamamuro, T., Fujishiro, N., Enya, K., Guyon, O., Kotani, T., Nishikawa, J., Sarugaku, Y., Takahashi, A., Wada, T., Burgarella, D., Team, O., & Team, {. S. (2018, mar). Mid-Infrared Imager, Spectrometer, Coronagraph (MISC) for the Origins Space Telescope (OST). In The Cosmic Wheel and the Legacy of the AKARI Archive: From Galaxies and Stars to Planets and Life.
• Schatz, L., Males, J., Close, L., Durney, O., Guyon, O., Hart, M., Lumbres, J., Miller, K., Knight, J., Rodack, A., Long, J., Van Gorkom, K., Jean, M., & Kautz, M. (2018, jul). Design of the MagAO-X pyramid wavefront sensor. In Adaptive Optics Systems VI, 10703.
• Sherwood Lollar, B., Atreya, S., Boss, A., Falkowski, P., Farmer, J., Guyon, O., Joyce, G., Kasting, J., Meadows, V., Neches, P., Pilcher, C., Renno, N., Rogers, K., Schmidt, B., Summons, R., Westall, F., & Wright, S. (2018, dec). Astrobiology Science Strategy for the Search for Life in the Universe. In AGU Fall Meeting Abstracts, 2018.
• Skemer, A., Stelter, D., Mawet, D., Fitzgerald, M., Mazin, B., Guyon, O., Marois, C., Briesemeister, Z., Brandt, T., Chilcote, J., Delorme, J., Jovanovic, N., Lu, J., Millar-Blanchaer, M. .., Wallace, J., Vasisht, G., Roberts, L., & Wang, J. (2018, jul). The planetary systems imager: 2-5 micron channel. In Ground-based and Airborne Instrumentation for Astronomy VII, 10702.
• Snik, F., Absil, O., Baudoz, P., Beaulieu, M., Bendek, E., Cady, E., Carlomagno, B., Carlotti, A., Cvetojevic, N., Doelman, D., Fogarty, K., Galicher, R., Guyon, O., Haffert, S., Huby, E., Jewell, J., Jovanovic, N., Keller, C., Kenworthy, M., , Knight, J., et al. (2018, jul). Review of high-contrast imaging systems for current and future ground-based and space-based telescopes III: technology opportunities and pathways. In Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III, 10706.
• Tuthill, P., Bendek, E., Guyon, O., Horton, A., Jeffries, B., Jovanovic, N., Klupar, P., Larkin, K., Norris, B., Pope, B., & Shao, M. (2018, jul). The TOLIMAN space telescope. In Optical and Infrared Interferometry and Imaging VI, 10701.
• Van Gorkom, K., Miller, K., Males, J., Guyon, O., Rodack, A., Lumbres, J., & Knight, J. (2018, jul). Characterization of deformable mirrors for the MagAO-X project. In Adaptive Optics Systems VI, 10703.
• Bendek, E., Belikov, R., Finan, E., Guyon, O., Pluzhnik, E., & Ammons, S. (2017, jan). "Exoplanet mass determination using precision imaging astrometry and coronagraphy". In American Astronomical Society Meeting Abstracts #229, 229.
• Bendek, E., Belikov, R., Pluzhnik, E., Guyon, O., Milster, T., Johnson, L., Finan, E., Knight, J., & Rodack, A. (2017, sep). "Results of the astrometry and direct imaging testbed for exoplanet detection". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10400.
• Currie, T., Guyon, O., Jovanovic, N., Lozi, J., Tamura, M., Kudo, T., Uyama, T., & Garcia, E. (2017, jan). "Directly Imaging Planets with SCExAO: First Results". In American Astronomical Society Meeting Abstracts #229, 229.
• Groff, T., Chilcote, J., Brandt, T., Kasdin, N., Galvin, M., Loomis, C., Rizzo, M., Knapp, G., Guyon, O., Jovanovic, N., Lozi, J., Currie, T., Takato, N., & Hayashi, M. (2017, sep). "First light of the CHARIS high-contrast integral-field spectrograph". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10400.
• Groff, T., Chilcote, J., Kasdin, J., Brandt, T., Galvin, M., Loomis, C., Carr, M., Knapp, G., Guyon, O., Jovanovic, N., Lozi, J., Takato, N., & Hayashi, M. (2017, jan). "On-Sky Performance Verification of the CHARIS IFS". In American Astronomical Society Meeting Abstracts #229, 229.
• Groff, T., Mejia Prada, C., Cady, E., Rizzo, M., Mandell, A., Gong, Q., McElwain, M., Zimmerman, N., Saxena, P., & Guyon, O. (2017, sep). "Wavefront control methods for high-contrast integral field spectroscopy". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10400.
• Knight, J., Brewer, J., Hamilton, R., Ward, K., Milster, T., & Guyon, O. (2017, sep). "Design, fabrication, and testing of stellar coronagraphs for exoplanet imaging". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10400.
• Meyer, M., Quanz, S., Kasper, M., Guyon, O., & Monnier, J. (2017, nov). Blazing a Trail: Towards Imaging Super-Earths from the Ground and Space. In Habitable Worlds 2017: A System Science Workshop, 2042.
• Newman, K., Belikov, R., & Guyon, O. (2017, nov). "Performance characterization of a phase-induced amplitude apodization complex focal plane mask". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10563.
• Pueyo, L., Zimmerman, N., Bolcar, M., Groff, T., Stark, C., Ruane, G., Jewell, J., Soummer, R., St.~Laurent, K., Wang, J., Redding, D., Mazoyer, J., Fogarty, K., Juanola-Parramon, R. .., Domagal-Goldman, S. .., Roberge, A., Guyon, O., & Mandell, A. (2017, sep). "The LUVOIR architecture ``A'' coronagraph instrument". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10398.
• Schatz, L. H., Males, J. R., Hart, M., Durney, O. F., Close, L. M., Guyon, O., Morzinski, K. M., Lumbres, J. R., & Miller, K. L. (2017, June). Pyramid Wavefront Sensing for Extreme Adaptive Optics. In AO4ELT5.
• Ammons, S. M., Garcia, E. V., Salama, M., Neichel, B., Lu, J., Marois, C., Macintosh, B., Savransky, D., Bendek, E., Guyon, O., Marin, E., Garrel, V., & Sivo, G. (2016, jul). Precision astrometry with adaptive optics: constraints on the mutual orbit of Luhman 16AB from GeMS. In Adaptive Optics Systems V, 9909.
• Domagal-Goldman, S., Gaudi, B., Seager, S., Mennesson, B., Warfield, K., Cahoy, K., Feinberg, L., Guyon, O., Kasdin, N., Mawet, D., Robinson, T., Rogers, L., Scowen, P., Somerville, R., Stapelfeldt, K., Stern, D., Turnbull, M., Marois, C., Mouillet, D., , Prusti, T., et al. (2016, dec). HabEx: Finding and characterizing Habitable Exoplanets with a potential future flagship astrophysics mission. In AGU Fall Meeting Abstracts.
• Farinato, J., Bacciotti, F., Baffa, C., Baruffolo, A., Bergomi, M., Bongiorno, A., Carbonaro, L., Carolo, E., Carlotti, A., Centrone, M., Close, L., De, P. M., Dima, M., D'Orazi, V., Esposito, S., Fantinel, D., Farisato, G., Gaessler, W., Giallongo, E., , Greggio, D., et al. (2016, jul). SHARK-NIR: from K-band to a key instrument, a status update. In Adaptive Optics Systems V, 9909.
• Feinberg, L., Rioux, N., Bolcar, M., Liu, A., Guyon, O., Stark, C., & Arenberg, J. (2016, jul). End-to-end assessment of a large aperture segmented ultraviolet optical infrared (UVOIR) telescope architecture. In Space Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave, 9904.
• Gee, W. T., Guyon, O., Walawender, J., Jovanovic, N., & Boucher, L. (2016, aug). Project PANOPTES: a citizen-scientist exoplanet transit survey using commercial digital cameras. In Ground-based and Airborne Instrumentation for Astronomy VI, 9908.
• Goebel, S. B., Guyon, O., Hall, D. N., Jovanovic, N., & Atkinson, D. E. (2016, jul). Evolutionary timescales of AO-produced speckles at NIR wavelengths. In Adaptive Optics Systems V, 9909.
• Groff, T. D., Chilcote, J., Kasdin, N. J., Galvin, M., Loomis, C., Carr, M. A., Brandt, T., Knapp, G., Limbach, M. A., Guyon, O., Jovanovic, N., McElwain, M. W., Takato, N., & Hayashi, M. (2016, aug). Laboratory testing and performance verification of the CHARIS integral field spectrograph. In Ground-based and Airborne Instrumentation for Astronomy VI, 9908.
• Groff, T. D., Kasdin, N. J., Galvin, M., Peters, M. A., Chilcote, J. K., Brandt, T., Knapp, G. R., Carr, M., Loomis, C., McElwain, M. W., Mede, K., Guyon, O., Jovanovic, N., Takato, N., & Hayashi, M. (2016, jan). Laboratory Performance and Commissioning of the CHARIS IFS. In American Astronomical Society Meeting Abstracts \#227, 227.
• Jovanovic, N., Cvetojevic, N., Schwab, C., Norris, B., Lozi, J., Gross, S., Betters, C., Singh, G., Guyon, O., Martinache, F., Doughty, D., & Tuthill, P. (2016, aug). Efficiently feeding single-mode fiber photonic spectrographs with an extreme adaptive optics system: on-sky characterization and preliminary spectroscopy. In Ground-based and Airborne Instrumentation for Astronomy VI, 9908.
• Jovanovic, N., Guyon, O., Lozi, J., Currie, T., Hagelberg, J., Norris, B., Singh, G., Pathak, P., Doughty, D., Goebel, S., Males, J., Kuhn, J., Serabyn, E., Tuthill, P., Schworer, G., Martinache, F., Kudo, T., Kawahara, H., Kotani, T., , Ireland, M., et al. (2016, jul). The SCExAO high contrast imager: transitioning from commissioning to science. In Adaptive Optics Systems V, 9909.
• Kern, B. D., Guyon, O., Belikov, R., Wilson, D., & Poberezhskiy, I. (2016, jan). PIAACMC coronagraph on WFIRST-AFTA. In American Astronomical Society Meeting Abstracts \#227, 227.
• Lozi, J., Guyon, O., Jovanovic, N., Singh, G., Goebel, S., Norris, B., & Okita, H. (2016, jul). Characterizing and mitigating vibrations for SCExAO. In Adaptive Optics Systems V, 9909.
• Males, J. R., Close, L. M., Guyon, O., Morzinski, K. M., Hinz, P., Esposito, S., Pinna, E., Xompero, M., Briguglio, R., Riccardi, A., Puglisi, A., Mazin, B., Ireland, M. J., Weinberger, A., Conrad, A. l., Kenworthy, M., Snik, F., Otten, G., Jovanovic, N., & Lozi, J. (2016, jul). The path to visible extreme adaptive optics with MagAO-2K and MagAO-X. In Adaptive Optics Systems V, 9909.
• Martinache, F., Jovanovic, N., & Guyon, O. (2016, jul). Subaru Coronagraphic eXtreme Adaptive Optics: on-sky performance of the asymmetric pupil Fourier wavefront sensor. In Adaptive Optics Systems V, 9909.
• Mawet, D., Wizinowich, P., Dekany, R., Chun, M., Hall, D., Cetre, S., Guyon, O., Wallace, J., Bowler, B., Liu, M., Ruane, G., Serabyn, E., Bartos, R., Wang, J., Vasisht, G., Fitzgerald, M., Skemer, A., Ireland, M., Fucik, J., , Fortney, J., et al. (2016, jul). Keck Planet Imager and Characterizer: concept and phased implementation. In Adaptive Optics Systems V, 9909.
• Mennesson, B., Gaudi, S., Seager, S., Cahoy, K., Domagal-Goldman, S., Feinberg, L., Guyon, O., Kasdin, J., Marois, C., Mawet, D., Tamura, M., Mouillet, D., Prusti, T., Quirrenbach, A., Robinson, T., Rogers, L., Scowen, P., Somerville, R., Stapelfeldt, K., , Stern, D., et al. (2016, jul). The Habitable Exoplanet (HabEx) Imaging Mission: preliminary science drivers and technical requirements. In Space Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave, 9904.
• Miller, K., & Guyon, O. (2016, jul). Linear dark field control: simulation for implementation and testing on the UA wavefront control testbed. In Adaptive Optics Systems V, 9909.
• Newman, K., Sirbu, D., Belikov, R., & Guyon, O. (2016, jul). Development of PIAA Complex Mask Coronagraphs for large aperture ground-based telescopes. In Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation II, 9912.
• Pathak, P., Guyon, O., Jovanovic, N., Lozi, J., Martinache, F., Minowa, Y., Kudo, T., Takami, H., Hayano, Y., & Narita, N. (2016, jul). First on-sky closed loop measurement and correction of atmospheric dispersion. In Adaptive Optics Systems V, 9909.
• Rains, A., Ireland, M., Jovanovic, N., Feger, T., Bento, J., Schwab, C., Coutts, D., Guyon, O., Arriola, A., & Gross, S. (2016, aug). "Precision single mode fibre integral field spectroscopy with the RHEA spectrograph". In Ground-based and Airborne Instrumentation for Astronomy VI, 9908.
• Rezaei, M., Park, M., Wheaton, S., Tan, C. L., Fathipour, V., Guyon, O., Ulmer, M. P., & Mohseni, H. (2016, jul). New progress in electron-injection detectors for NIR imagers with low noise and high frame rates. In High Energy, Optical, and Infrared Detectors for Astronomy VII, 9915.
• Schwab, C., Jovanovic, N., Feger, T., Bakovic, M., Gurevich, Y., St{\"urmer}, J., Apodaca, R., Vanzi, L., Rukdee, S., Lawrence, J., Coutts, D., Cvetojevic, N., Mahadevan, S., Stef{\'ansson}, G., Halverson, S., & Guyon, O. (2016, jul). Adaptive optics fed single-mode spectrograph for high-precision Doppler measurements in the near-infrared. In Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation II, 9912.
• Singh, G., Lozi, J., Choquet, E., Serabyn, E., & Guyon, O. (2016, jul). PSF calibration using the Lyot-based low order wavefront sensor telemetry: first simulations. In Adaptive Optics Systems V, 9909.
• Wizinowich, P., Chun, M., Mawet, D., Agapito, G., Dekany, R., Esposito, S., Fusco, T., Guyon, O., Hall, D., Plantet, C., & Rigaut, F. (2016, jul). Near-infrared wavefront sensing. In Adaptive Optics Systems V, 9909.
• Farinato, J., Baffa, C., Baruffolo, A., Bergomi, M., Carbonaro, L., Carolo, E., Carlotti, A., Centrone, M., Close, L., De, P. M., Dima, M., Esposito, S., Fantinel, D., Farisato, G., Gaessler, W., Giallongo, E., Greggio, D., Guyon, O., Hinz, P., , Lisi, F., et al. (2015, oct). SHARK-NIR Channel: a high contrast imager with coronagraphic capabilities for the Large Binocular Telescope. In Adaptive Optics for Extremely Large Telescopes IV (AO4ELT4).
• Gee}, W. T., Walawender, J., Butterfield, M., Guyon, O., Jovanovic, N., & Team, {. (2015, jan). Building POCS: An open source observatory control system for amateur telescopes used by the PANOPTES project for the detection of extrasolar planets. In American Astronomical Society Meeting Abstracts \#225, 225.
• Groff, T. D., Kasdin, N. J., Limbach, M. A., Galvin, M., Carr, M. A., Knapp, G., Brandt, T., Loomis, C., Jarosik, N., Mede, K., McElwain, M. W., Leviton, D. B., Miller, K. H., Quijada, M. A., Guyon, O., Jovanovic, N., Takato, N., & Hayashi, M. (2015, sep). The CHARIS IFS for high contrast imaging at Subaru. In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Groff, T. D., Kasdin, N. J., Peters, M. A., Galvin, M., Knapp, G. R., Brandt, T., Loomis, C., Carr, M., Mede, K., Jarosik, N., McElwain, M. W., Guyon, O., Jovanovic, N., Takato, N., & Hayashi, M. (2015, jan). CHARIS Construction Status, Design, and Future Science. In American Astronomical Society Meeting Abstracts \#225, 225.
• Guyon, O., Jovanovic, N., & Lozi, J. (2015, dec). Direct imaging and spectroscopic characterization of habitable planets with ELTs. In AAS/Division for Extreme Solar Systems Abstracts, 47.
• Lozi, J., Guyon, O., Jovanovic, N., Singh, G., Doughty, D., Pathak, P., Goebel, S., & Kudo, T. (2015, dec). SCExAO: the most complete instrument to characterize exoplanets and stellar environments. In AAS/Division for Extreme Solar Systems Abstracts, 47.
• Lozi, J., Jovanovic, N., Guyon, O., Males, J., Singh, G., Doughty, D., PAthak, P., Goebel, S., Kudo, T., & artinache, F. (2015, oct). SCExAO: the first high contrast exoplanet imager on an ELT?. In Adaptive Optics for Extremely Large Telescopes IV (AO4ELT4).
• Mazin, B. A., Meeker, S., Strader, M., Szypryt, P., Walter, A., Bockstiegel, C., Collura, G., Mawet, D., Jensen-Clem, R., Guyon, O., Jovanovic, N., Oppenheimer, R., & Serabyn, E. (2015, dec). MKIDs for Direct Imaging of Exoplanets. In AAS/Division for Extreme Solar Systems Abstracts, 47.
• Mendillo, C. B., Brown, J., Martel, J., Howe, G. A., Hewasawam, K., Finn, S. C., Cook, T. A., Chakrabarti, S., Douglas, E. S., Mawet, D., Guyon, O., Singh, G., Lozi, J., Cahoy, K. L., & Marinan, A. D. (2015, sep). The low-order wavefront sensor for the PICTURE-C mission. In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Miller, K., Guyon, O., Codona, J., Knight, J., & Rodack, A. (2015, sep). UA wavefront control lab: design overview and implementation of new wavefront sensing techniques. In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Newman, K., Belikov, R., Guyon, O., & Pluzhnik, E. (2015, jan). Performance characterization of a PIAA complex focal plane mask. In American Astronomical Society Meeting Abstracts \#225, 225.
• Pluzhnik, E., Guyon, O., Belikov, R., & Bendek, E. (2015, sep). Design of off-axis PIAACMC mirrors. In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Poberezhskiy, I., Poberezhskiy, I., Zhao, F., An, X., Balasubramanian, K., Belikov, R., Cady, E., Diaz, R., Gordon, B., Guyon, O., Kasdin, N. J., Kern, B., Kuhnert, A., Moody, D., Muller, R., Nemati, B., Patterson, K., Riggs, A., Ryan, D., , Seo, B., et al. (2015, jan). First Year of WFIRST/AFTA Coronagraph Technology Development: Testbed Progress Update. In American Astronomical Society Meeting Abstracts \#225, 225.
• Rodack, A. T., Knight, J. M., Codona, J. L., Miller, K. L., & Guyon, O. (2015, sep). Adaptive optics self-calibration using differential OTF (dOTF). In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Sirbu, D., Thomas, S. J., Belikov, R., Lozi, J., Bendek, E., Pluzhnik, E., Lynch, D. H., Hix, T., Zell, P., Guyon, O., & Schneider, G. (2015, November 20). EXCEDE technology development IV: demonstration of polychromatic contrast in vacuum at 1.2 L/D. In Techniques and Instrumentation for Detection of Exoplanets VII (SPIE Proc. Series), 9605.
• Sirbu, D., Thomas, S. J., Belikov, R., Lozi, J., Bendek, E., Pluzhnik, E., Lynch, D. H., Hix, T., Zell, P., Schneider, G., & Guyon, O. (2015, sep). EXCEDE technology development IV: demonstration of polychromatic contrast in vacuum at 1.2 \ensuremath{\lambda}/D. In Techniques and Instrumentation for Detection of Exoplanets VII, 9605.
• Tumlinson, J., Seager, S., Dalcanton, J., Postman, M., Aigrain, S., battel, S., Brandt, W. N., Conroy, C., Feinberg, L., Gezari, S., Guyon, O., Harris, W. M., Hirata, C., Mather, J. C., Redding, D., Schiminovich, D., & Stahl, H. P. (2015, jan). Beyond JWST: Science Drivers for the Next Great UVOIR Space Telescope. In American Astronomical Society Meeting Abstracts \#225, 225.
• Ammons, S. M., Bendek, E. A., Guyon, O., Macintosh, B., & Savransky, D. (2014, apr). Microarcsecond Astrometry with MCAO Using a Diffractive Mask. In Formation, Detection, and Characterization of Extrasolar Habitable Planets, 293.
• Ammons, S., Macintosh, B., Savransky, D., Marois, C., Neichel, B., Guyon, O., & Bendek, E. (2014, jan). On-Sky Tests of High Precision Astrometry and Implications for Exoplanet Mass Measurement. In American Astronomical Society Meeting Abstracts \#223, 223.
• Ammons, S., Macintosh, B., Savransky, D., Marois, C., Neichel, B., Guyon, O., & Bendek, E. (2014, jan). On-Sky Tests of High Precision Astrometry and Implications for Exoplanet Mass Measurement. In American Astronomical Society Meeting Abstracts, 223, #229.04.
• Ammons, S., Neichel, B., Lu, J., Gavel, D. T., Srinath, S., McGurk, R., Rudy, A., Rockosi, C., Marois, C., Macintosh, B., Savransky, D., Galicher, R., Bendek, E., Guyon, O., Marin, E., Garrel, V., & Sivo, G. (2014, aug). A measurement of the systematic astrometric error in GeMS and the short-term astrometric precision in ShaneAO. In Adaptive Optics Systems IV, 9148.
• Belikov, R., Bendek, E., Davis, P., Duncan, A., Greene, T. P., Guyon, O., Hix, T., Irwin, W., Kendrick, R., Lozi, J., Lynch, D., Mihara, R., Pluzhnik, E., Schneider, G., Smith, E., Thomas, S., & Witteborn, F. C. (2014, jan). Technology Demonstration Milestone #1 for the EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) I. Laboratory/Experimental Results. In American Astronomical Society Meeting Abstracts, 223, #109.02.
• Belikov, R., Lozi, J., Pluzhnik, E., Hix, T. T., Bendek, E., Thomas, S. J., Lynch, D. H., Mihara, R., Irwin, J. W., Duncan, A. L., Greene, T. P., Guyon, O., Kendrick, R. L., Smith, E. H., Witteborn, F. C., & Schneider, G. (2014, aug). EXCEDE technology development III: first vacuum tests. In Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 9143.
• Bendek, E., Ennico, K., Rademacher, A., Lynch, D., & Guyon, O. (2014, jan). Astrometry with small-size collapsible space telescope. In American Astronomical Society Meeting Abstracts \#223, 223.
• Bendek, E., Ennico, K., Rademacher, A., Lynch, D., & Guyon, O. (2014, jan). Astrometry with small-size collapsible space telescope. In American Astronomical Society Meeting Abstracts, 223, #149.22.
• Brandt, T. D., McElwain, M. W., Janson, M., Knapp, G. R., Mede, K., Limbach, M. A., Groff, T., Burrows, A., Gunn, J. E., Guyon, O., Hashimoto, J., Hayashi, M., Jovanovic, N., Kasdin, N., Kuzuhara, M., Lupton, R. H., Martinache, F., Sorahana, S., Spiegel, D. S., , Takato, N., et al. (2014, jul). CHARIS science: performance simulations for the Subaru Telescope's third-generation of exoplanet imaging instrumentation. In Adaptive Optics Systems IV, 9148.
• Currie, T., Guyon, O., Martinache, F., Clergeon, C., McElwain, M., Thalmann, C., Jovanovic, N., Singh, G., & Kudo, T. (2014, jan). SCExAO: First Results and On-Sky Performance. In Exploring the Formation and Evolution of Planetary Systems, 299.
• Farinato, J., Pedichini, F., Pinna, E., Baciotti, F., Baffa, C., Baruffolo, A., Bergomi, M., Bruno, P., Cappellaro, E., Carbonaro, L., Carlotti, A., Centrone, M., Close, L., Codona, J., Desidera, S., Dima, M., Esposito, S., Fantinel, D., Farisato, G., , Fontana, A., et al. (2014, aug). SHARK (System for coronagraphy with High order Adaptive optics from R to K band): a proposal for the LBT 2nd generation instrumentation. In Ground-based and Airborne Instrumentation for Astronomy V, 9147.
• Groff, T. D., Kasdin, N., Limbach, M. A., Galvin, M., Carr, M. A., Knapp, G., Brandt, T., Loomis, C., Jarosik, N., Mede, K., McElwain, M. W., Janson, M., Guyon, O., Jovanovic, N., Takato, N., Martinache, F., & Hayashi, M. (2014, jul). Construction and status of the CHARIS high contrast imaging spectrograph. In Ground-based and Airborne Instrumentation for Astronomy V, 9147.
• Groff, T. D., Peters, M., Kasdin, N., Galvin, M., Brandt, T., Carr, M., Knapp, G., McElwain, M., Janson, M., Loomis, C., Guyon, O., Martinache, F., Jovanovic, N., Mede, K., Takato, N., & Hayashi, M. (2014, jan). Final Design of the CHARIS Integral Field Spectrograph for the Subaru Telescope. In American Astronomical Society Meeting Abstracts \#223, 223.
• Guyon, O. (2014, mar). Coronagraphy -- From State of the Art to the Near Future. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \& Instruments.
• Guyon, O., Hayano, Y., Tamura, M., Kudo, T., Oya, S., Minowa, Y., Lai, O., Jovanovic, N., Takato, N., Kasdin, J., Groff, T., Hayashi, M., Arimoto, N., Takami, H., Bradley, C., Sugai, H., Perrin, G., Tuthill, P., & Mazin, B. (2014, aug). Adaptive optics at the Subaru telescope: current capabilities and development. In Adaptive Optics Systems IV, 9148.
• Guyon, O., Walawender, J., Jovanovic, N., Butterfield, M., Gee, W. T., & Mery, R. (2014, jul). The PANOPTES project: discovering exoplanets with low-cost digital cameras. In Ground-based and Airborne Telescopes V, 9145.
• Hinz, P., Esposito, S., Apai, D., Brusa, G., Close, L., Guyon, O., Hill, J., Males, J., Pinna, E., & Puglisi, A. (2014, jul). Toward visible wavelength coherent imaging with the LBT. In Optical and Infrared Interferometry IV, 9146.
• Jovanovic, N., Guyon, O., Martinache, F., Clergeon, C., Singh, G., Kudo, T., Newman, K., Kuhn, J., Serabyn, E., Norris, B., Tuthill, P., Stewart, P., Huby, E., Perrin, G., Lacour, S., Vievard, S., Murakami, N., Fumika, O., Minowa, Y., , Hayano, Y., et al. (2014, jul). Development and recent results from the Subaru coronagraphic extreme adaptive optics system. In Ground-based and Airborne Instrumentation for Astronomy V, 9147.
• Jovanovic, N., Guyon, O., Martinache, F., Schwab, C., & Cvetojevic, N. (2014, jul). How to inject light efficiently into single-mode fibers. In Ground-based and Airborne Instrumentation for Astronomy V, 9147.
• Kasdin, N. J., Guyon, O., Greene, T. P., Macintosh, B., & Traub, W. A. (2014, jan). Coronagraphy on AFTA-WFIRST. In American Astronomical Society Meeting Abstracts, 223, #341.03.
• Kasdin, N., Guyon, O., Greene, T., Macintosh, B., & Traub, W. (2014, jan). Coronagraphy on AFTA-WFIRST. In American Astronomical Society Meeting Abstracts \#223, 223.
• Kotani, T., Tamura, M., Suto, H., Nishikawa, J., Sato, B., Aoki, W., Usuda, T., Kurokawa, T., Kashiwagi, K., Nishiyama, S., Ikeda, Y., Hall, D. B., Hodapp, K. W., Hashimoto, J., Morino, J., Okuyama, Y., Tanaka, Y., Suzuki, S., Inoue, S., , Kwon, J., et al. (2014, jul). Infrared Doppler instrument (IRD) for the Subaru telescope to search for Earth-like planets around nearby M-dwarfs. In Ground-based and Airborne Instrumentation for Astronomy V, 9147.
• Lozi, J., Belikov, R., Bendek, E., Davis, P., Duncan, A., Greene, T., Guyon, O., Hix, T., Irwin, W., Kendrick, R., Lynch, D., Mihara, R., PIuzhnik, E., Schneider, G., Smith, E., Thomas, S., & Witteborn, F. (2014, mar). EXoplanetary Circumstellar Environments and Disk Explorer technology demonstration: Experimental results in air and vacuum. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \& Instruments.
• Lozi, J., Belikov, R., Schneider, G., Guyon, O., Thomas, S., Pluzhnik, E., & Team, E. P. (2014, jan). Experimental study of a low-order wavefront sensor for high-contrast coronagraphic imagers. In American Astronomical Society Meeting Abstracts, 223, #105.09.
• Lozi, J., Belikov, R., Thomas, S. J., Pluzhnik, E., Bendek, E., Guyon, O., & Schneider, G. (2014, aug). Experimental study of a low-order wavefront sensor for high-contrast coronagraphic imagers: results in air and in vacuum. In Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 9143.
• Lozi}, J., Belikov, R., Schneider, G., Guyon, O., Thomas, S., Pluzhnik, E., & Team, {. (2014, jan). Experimental study of a low-order wavefront sensor for high-contrast coronagraphic imagers. In American Astronomical Society Meeting Abstracts \#223, 223.
• Males, J. R., Close, L. M., Guyon, O., Morzinski, K., Puglisi, A., Hinz, P., Follette, K. B., Monnier, J. D., Tolls, V., Rodigas, T. J., Weinberger, A., Boss, A., Kopon, D., Wu, Y., Esposito, S., Riccardi, A., Xompero, M., Briguglio, R., & Pinna, E. (2014, jul). Direct imaging of exoplanets in the habitable zone with adaptive optics. In Adaptive Optics Systems IV, 9148.
• Males, J., Close, L., Guyon, O., & Barman, T. (2014, mar). Direct Imaging of Extrasolar Giant Planets in the Habitable Zone. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \& Instruments.
• Martinache, F., Guyon, O., Jovanovic, N., Clergeon, C., Singh, G., & Kudo, T. (2014, aug). On-sky speckle nulling with the Subaru Coronagraphic Extreme AO (SCExAO) instrument. In Adaptive Optics Systems IV, 9148.
• Mateen, M., Guyon, O., Hart, M., & Codona, J. (2014, sep). A Wavefront Sensor to Detect Dim Objects. In Advanced Maui Optical and Space Surveillance Technologies Conference.
• Mazin, B., Eyken, J. v., Meeker, S., Jensen-Clem, R. .., Oppenheimer, B., & Guyon, O. (2014, mar). MKIDs for Direct Imaging of Exoplanets. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \& Instruments.
• Murakami, N., Nishikawa, J., Tamura, M., Serabyn, E., Traub, W. A., Liewer, K. M., Moody, D. C., Trauger, J. T., Guyon, O., Martinache, F., Jovanovic, N., Singh, G., Oshiyama, F., Shoji, H., Sakamoto, M., Hamaguchi, S., Oka, K., & Baba, N. (2014, aug). Recent progress on phase-mask coronagraphy based on photonic-crystal technology. In Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 9143.
• Newman, K., Guyon, O., Balasubramanian, K., & Wilson, D. (2014, jan). A focal plane mask for the PIAA Complex Mask Coronagraph. In American Astronomical Society Meeting Abstracts \#223, 223.
• Newman, K., Guyon, O., Balasubramanian, K., & Wilson, D. (2014, jan). A focal plane mask for the PIAA Complex Mask Coronagraph. In American Astronomical Society Meeting Abstracts, 223, #348.13.
• Norris, B. R., Tuthill, P. G., Jovanovic, N., Schworer, G., Guyon, O., Martinache, F., & Stewart, P. N. (2014, jul). VAMPIRES: probing the innermost regions of protoplanetary systems with polarimetric aperture-masking. In Optical and Infrared Interferometry IV, 9146.
• Poberezhskiy, I., Zhao, F., An, X., Balasubramanian, K., Belikov, R., Cady, E., Demers, R., Diaz, R., Gong, Q., Gordon, B., Goullioud, R., Greer, F., Guyon, O., Hoenk, M., Kasdin, N. J., Kern, B., Krist, J., Kuhnert, A., McElwain, M., , Mennesson, B., et al. (2014, aug). Technology development towards WFIRST-AFTA coronagraph. In Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 9143.
• Schneider, G. H., Belikov, R., Guyon, O., Lozi, J., Eduardo, B., Davis, P., Greene, T. P., Lynch, D., Eugene, P., Sandrine, T., Witteborn, F., Duncan, A., Kendrick, R., Hix, T., Mihara, R., Smith, E., Irwin, W., Debes, J. H., Carson, J., , Hines, D. C., et al. (2014, Jan.). Technology Demonstration Milestone #1 for the EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) II. Science Drivers and Implications. In American Astronomical Society Meeting Abstracts, 223, #149.08.
• Schneider, G., Belikov, R., Guyon, O., Lozi, J., Eduardo, B., Davis, P., Greene, T. P., Lynch, D., Eugene, P., Sandrine, T., Witteborn, F., Duncan, A., Kendrick, R., Hix, T., Mihara, R., Smith, E., Irwin, W., Debes, J. H., Carson, J., , Hines, D. C., et al. (2014, jan). Technology Demonstration Milestone #1 for the EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) II. Science Drivers and Implications. In American Astronomical Society Meeting Abstracts, 223, #149.08.
• Schneider}, G., Belikov, R., Guyon, O., Lozi, J., Eduardo, B., Davis, P., Greene, T., Lynch, D., Eugene, P., Sandrine, T., Witteborn, F., Duncan, A., Kendrick, R., Hix, T., Mihara, R., Smith, E., Irwin, W., Debes, J., Carson, J., , Hines, D., et al. (2014, jan). Technology Demonstration Milestone \#1 for the EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) II. Science Drivers and Implications. In American Astronomical Society Meeting Abstracts \#223, 223.
• Singh, G., Guyon, O., Baudoz, P., Jovanovich, N., Martinache, F., Kudo, T., Serabyn, E., & Kuhn, J. G. (2014, aug). Lyot-based low order wavefront sensor: implementation on the Subaru Coronagraphic Extreme Adaptive Optics System and its laboratory performance. In Adaptive Optics Systems IV, 9148.
• Singh, G., Guyon, O., Baudoz, P., Martinache, F., Jovanovic, N., & Clergeon, C. (2014, mar). Lyot-based low order wavefront sensor for Phase Mask Coronagraphs. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \& Instruments.
• Traub, W. A., Belikov, R., Guyon, O., Kasdin, N. J., Krist, J., Macintosh, B., Mennesson, B., Savransky, D., Shao, M., Serabyn, E., & Trauger, J. (2014, aug). Science yield estimation for AFTA coronagraphs. In Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 9143.
• Ammons, S. M., Bendek, E., Guyon, O., Macintosh, B., Marois, C., Neichel, B., Galicher, R., & Savransky, D. (2013, dec). Two Pathfinder Tests of High Precision Astrometry On-Sky. In Proceedings of the Third AO4ELT Conference.
• Ammons, S., Bendek, E., Macintosh, B., & Guyon, O. (2013, jan). On-sky Tests of High-Precision Astrometry Using a Diffractive Mask. In American Astronomical Society Meeting Abstracts \#221, 221.
• Ammons, S., Bendek, E., Macintosh, B., & Guyon, O. (2013, jan). On-sky Tests of High-Precision Astrometry Using a Diffractive Mask. In American Astronomical Society Meeting Abstracts, 221, #419.02.
• Balasubramanian, K., Wilson, D., White, V., Muller, R., Dickie, M., Yee, K., Ruiz, R., Shaklan, S., Cady, E., Kern, B., Belikov, R., Guyon, O., & Kasdin, N. J. (2013, sep). High contrast internal and external coronagraph masks produced by various techniques. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Belikov, R., Bendek, E., Greene, T. P., Guyon, O., Lozi, J., Lynch, D. H., Newman, K. E., Pluzhnik, E., Schneider, G., Tenerelli, D., Thomas, S. J., & Witteborn, F. C. (2013, sep). EXCEDE technology development II: demonstration of high contrast at 1.2 \ensuremath{\lambda}/D and preliminary broadband results. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Belikov, R., Pluzhnik, E., Lozi, J., Witteborn, F. C., Greene, T. P., Lynch, D. H., Schneider, G., Guyon, O., & Tenerelli, D. (2013, jan). EXCEDE Technology Development: Demonstrations of High Contrast at 1.2 $ lambda$/D and Fast Low-order Wavefront Control for an Explorer Space Telescope Mission. In American Astronomical Society Meeting Abstracts, 221, #305.02.
• Belikov, R., Pluzhnik, E., Lozi, J., Witteborn, F., Greene, T., Lynch, D., Schneider, G., Guyon, O., & Tenerelli, D. (2013, jan). EXCEDE Technology Development: Demonstrations of High Contrast at 1.2 \ensuremath{\lambda}/D and Fast Low-order Wavefront Control for an Explorer Space Telescope Mission. In American Astronomical Society Meeting Abstracts \#221, 221.
• Bendek, E. A., Guyon, O., Belikov, R., Ammons, S. M., Milster, T., Kim, Y., & Johnson, L. (2013, sep). Exoplanet detection and characterization using combined coronagraphy and sub-UAS astrometry from space. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Bendek, E., Belikov, R., & Guyon, O. (2013, jan). Obtaining Sub-uas Astrometry on a Wide-field, Coronagraph Equipped, Space Telescope Using a Diffractive Pupil. In American Astronomical Society Meeting Abstracts \#221, 221.
• Bendek, E., Belikov, R., & Guyon, O. (2013, jan). Obtaining Sub-uas Astrometry on a Wide-field, Coronagraph Equipped, Space Telescope Using a Diffractive Pupil. In American Astronomical Society Meeting Abstracts, 221, #328.05.
• Clergeon, C., Guyon, O., Martinache, F., Veran, J., Gendron, E., Rousset, G., Correia, C., & Garrel, V. (2013, dec). The Subaru Coronagraphic Extreme AO High Speed and High Sensitivity Wavefront Sensors. In Proceedings of the Third AO4ELT Conference.
• Correia, C., Veran, J., Guyon, O., & Clergeon, C. (2013, dec). Wave-front reconstruction for the non-linear curvature wave-front sensor. In Proceedings of the Third AO4ELT Conference.
• Groff, T. D., Peters, M. A., Kasdin, N. J., Knapp, G., Galvin, M., Carr, M., McElwain, M. W., Brandt, T., Janson, M., Gunn, J. E., Lupton, R., Guyon, O., Martinache, F., Jovanovic, N., Hayashi, M., & Takato, N. (2013, sep). Design of the CHARIS integral field spectrograph for exoplanet imaging. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Groff, T. D., Peters, M., Kasdin, N., McElwain, M., Galvin, M., Carr, M., Knapp, G., Janson, M., Brandt, T., Lupton, R., Gunn, J., Guyon, O., Martinache, F., Hayashi, M., & Takato, N. (2013, jan). Preliminary Design of the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS). In American Astronomical Society Meeting Abstracts \#221, 221.
• Guyon, O. (2013, sep). Imaging Earth-like planets around late-type stars with low-inner working angle PIAA coronagraphy. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Guyon, O., & Martinache, F. (2013, jan). How Extremely Large Telescopes (ELTs) will Acquire the First Spectra of Rocky Habitable Planets. In American Astronomical Society Meeting Abstracts \#221, 221.
• Guyon, O., & Martinache, F. (2013, jan). How Extremely Large Telescopes (ELTs) will Acquire the First Spectra of Rocky Habitable Planets. In American Astronomical Society Meeting Abstracts, 221, #419.05.
• Jovanovic, N., Guyon, O., Martinache, F., Clergeon, C., Singh, G., Vievard, S., Kudo, T., Garrel, V., Norris, B., Tuthill, P., Stewart, P., Huby, E., Perrin, G., & Lacour, S. (2013, dec). SCExAO as a precursor to an ELT exoplanet direct imaging instrument. In Proceedings of the Third AO4ELT Conference.
• Jovanovic, N., Martinache, F., Guyon, O., Clergeon, C., & Garrel, V. (2013, jan). The Subaru Coronagraphic Extreme AO Project: Progress and Upgrades. In American Astronomical Society Meeting Abstracts \#221, 221.
• Kern, B., Guyon, O., Kuhnert, A., Niessner, A., Martinache, F., & Balasubramanian, K. (2013, sep). Laboratory demonstration of Phase Induced Amplitude Apodization (PIAA) coronagraph with better than 10$^-9$ contrast. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Lawson, P., Belikov, R., Cash, W., Clampin, M., Glassman, T., Guyon, O., Kasdin, N., Kern, B., Lyon, R., Mawet, D., Moody, D., Samuele, R., Serabyn, E., Sirbu, D., & Trauger, J. (2013, sep). Survey of experimental results in high-contrast imaging for future exoplanet missions. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Lozi, J., Belikov, R., Schneider, G., Guyon, O., Pluzhnik, E., Thomas, S. J., & Martinache, F. (2013, sep). Experimental study of the low-order wavefront sensor for the high-contrast coronagraphic imager EXCEDE. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Lozi, J., Belikov, R., Schneider, G., Guyon, O., Pluzhnik, E., Thomas, S., & Martinache, F. (2013, dec). Experimental study of a low-order wavefront sensor for a high-contrast coronagraphic imager at 1.2 lambda/D. In Proceedings of the Third AO4ELT Conference.
• Mateen, M., Guyon, O., Hart, M., Johnson, R., & Spillar, E. (2013, sep). A Non-Lienar Curvature Wavefront Sensor to Detect Geos Without The Use of a Laser Guidestar. In Advanced Maui Optical and Space Surveillance Technologies Conference.
• Newman, K., Belikov, R., & Guyon, O. (2013, jan). Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy. In American Astronomical Society Meeting Abstracts \#221, 221.
• Newman, K., Belikov, R., Guyon, O., Balasubramanian, K., & Wilson, D. (2013, sep). Achromatic focal plane mask for exoplanet imaging coronagraphy. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Peters-Limbach, M. A., Groff, T. D., Kasdin, N. J., Driscoll, D., Galvin, M., Foster, A., Carr, M. A., LeClerc, D., Fagan, R., McElwain, M. W., Knapp, G., Brandt, T., Janson, M., Guyon, O., Jovanovic, N., Martinache, F., Hayashi, M., & Takato, N. (2013, sep). The optical design of CHARIS: an exoplanet IFS for the Subaru telescope. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Singh, G., Martinache, F., Baudoz, P., Guyon, O., Clergeon, C., & Matsuo, T. (2013, dec). Lyot-based ultra-fine pointing control system for phase mask coronagraphs. In Proceedings of the Third AO4ELT Conference.
• Thomas, S., Pluzhnik, E., Lozi, J., Belikov, R., Witteborn, F., Greene, T., Schneider, G., & Guyon, O. (2013, dec). Improving the broadband contrast at small inner working angles using image sharpening techniques. In Proceedings of the Third AO4ELT Conference.
• Thomas, S., Pluzhnik, E., Lozi, J., Belikov, R., Witteborn, F., Greene, T., Schneider, G., & Guyon, O. (2013, sep). Improving image contrast for the direct detection of exoplanets at small inner working angles. In Techniques and Instrumentation for Detection of Exoplanets VI, 8864.
• Ammons, S. M., Bendek, E. A., Guyon, O., Macintosh, B., & Savransky, D. (2012, jul). Theoretical limits on bright star astrometry with multi-conjugate adaptive optics using a diffractive pupil. In Adaptive Optics Systems III, 8447.
• Belikov, R., Pluzhnik, E., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., & Guyon, O. (2012, jan). PIAA Coronagraph Development at NASA Ames: High Contrast Laboratory Demonstration at Inner Working Angles Down to 1.2 l/D. In American Astronomical Society Meeting Abstracts #219, 219, #155.17.
• Belikov, R., Pluzhnik, E., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., Schneider, G., Guyon, O., & Tenerelli, D. (2012, sep). EXCEDE technology development I: first demonstrations of high contrast at 1.2 \ensuremath{\lambda}/D for an Explorer space telescope mission. In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• Belikov, R., Pluzhnik, E., Witteborn, F., Greene, T., Lynch, D., Zell, P., & Guyon, O. (2012, jan). PIAA Coronagraph Development at NASA Ames: High Contrast Laboratory Demonstration at Inner Working Angles Down to 1.2 l/D. In American Astronomical Society Meeting Abstracts \#219, 219.
• Bendek, E. A., Ammons, S. M., Belikov, R., Pluzhnik, E., & Guyon, O. (2012, sep). High precision astrometry laboratory demonstration for exoplanet detection using a diffractive pupil telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 8442.
• Bendek, E., Guyon, O., Shao, M., Ammons, M., Shaklan, S., Belikov, R., & Woodruff, R. (2012, jan). High precision astrometry with a Diffractive Pupil Telescope. In American Astronomical Society Meeting Abstracts #219, 219, #155.18.
• Bendek, E., Guyon, O., Shao, M., Ammons, M., Shaklan, S., Belikov, R., & Woodruff, R. (2012, jan). High precision astrometry with a Diffractive Pupil Telescope. In American Astronomical Society Meeting Abstracts \#219, 219.
• Blain, C., Guyon, O., Martinache, F., Bradley, C., & Clergeon, C. (2012, jul). Open-loop control of SCExAO's MEMS deformable mirror using the Fast Iterative Algorithm: speckle control performances. In Adaptive Optics Systems III, 8447.
• Carlotti, A., Kasdin, N. J., Martinache, F., Vanderbei, R. J., Young, E. J., Che, G., Groff, T. D., & Guyon, O. (2012, sep). Fully optimized shaped pupils: preparation for a test at the Subaru Telescope. In Ground-based and Airborne Instrumentation for Astronomy IV, 8446.
• Clergeon, C., Guyon, O., & Martinache, F. (2012, jan). The Subaru Coronagraphic Extreme Ao Project: First On-sky Results. In American Astronomical Society Meeting Abstracts \#219, 219.
• Guyon, O., & Martinache, F. (2012, sep). Achieving high precision photometry for transiting exoplanets with a low cost robotic DSLR-based imaging system. In Ground-based and Airborne Telescopes IV, 8444.
• Guyon, O., Bendek, E., Ammons, S. M., Shao, M., Shaklan, S., Woodruff, R. A., Belikov, R., & Milster, T. (2012, sep). Characterization of habitable exoplanets with simultaneous coronagraphy and astrometry with a single aperture telescope. In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• Guyon, O., Kern, B., Belikov, R., Shaklan, S., Kuhnert, A., Give'on, A., & Martinache, F. (2012, sep). Phase induced amplitude apodization (PIAA) coronagraphy: recent results and future prospects. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 8442.
• Guyon, O., Kern, B., Belikov, R., Shaklan, S., Kuhnert, A., Giveon, A., Martinache, F., Greene, T., & Pluzhnik, E. (2012, jan). High Contrast Imaging With Phase-induced Amplitude Apodization (PIAA). In American Astronomical Society Meeting Abstracts #219, 219, #155.15.
• Guyon, O., Kern, B., Belikov, R., Shaklan, S., Kuhnert, A., Giveon, A., Martinache, F., Greene, T., & Pluzhnik, E. (2012, jan). High Contrast Imaging With Phase-induced Amplitude Apodization (PIAA). In American Astronomical Society Meeting Abstracts \#219, 219.
• Guyon, O., Martinache, F., Cady, E. J., Belikov, R., Balasubramanian, K., Wilson, D., Clergeon, C. S., & Mateen, M. (2012, jul). How ELTs will acquire the first spectra of rocky habitable planets. In Adaptive Optics Systems III, 8447.
• Guyon, O., Schneider, G., Belikov, R., & Tenerelli, D. J. (2012, sep). The EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE). In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• Hinz, P., Codona, J., Guyon, O., Hoffmann, W., Skemer, A., Hora, J., Tolls, V., Boss, A., Weinberger, A., Arbo, P., Connors, T., Durney, O., McMahon, T., Montoya, M., & Vaitheeswaran, V. (2012, sep). TIGER: a high contrast infrared imager for the Giant Magellan Telescope. In Ground-based and Airborne Instrumentation for Astronomy IV, 8446.
• Kotani, T., Enya, K., Nakagawa, T., Matsuhara, H., Kataza, H., Kawada, M., Mita, M., Komatsu, K., Uchida, H., Fujiwara, K., Mitani, S., Sakai, S., Haze, K., Kaneda, H., Oyabu, S., Ishihara, D., Miyata, T., Sako, S., Nakamura, T., , Asano, K., et al. (2012, sep). SPICA coronagraph instrument: characterization of atmospheres and physical parameters of giant planets by direct imaging and spectroscopy. In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• Kulcs{\'ar}, C., Sivo, G., Raynaud, H., Neichel, B., Rigaut, F., Christou, J., Guesalaga, A., Correia, C., V{\'eran}, J., Gendron, E., Vidal, F., Rousset, G., Morris, T., Esposito, S., Quiros-Pacheco, F., Agapito, G., Fedrigo, E., Pettazzi, L., Clare, R., , Muradore, R., et al. (2012, jul). Vibrations in AO control: a short analysis of on-sky data around the world. In Adaptive Optics Systems III, 8447.
• Lawson, P. R., Poyneer, L., Barrett, H., Frazin, R., Caucci, L., Devaney, N., Furenlid, L., G{\ladysz}, S., Guyon, O., Krist, J., Maire, J., Marois, C., Mawet, D., Mouillet, D., Mugnier, L., Pearson, I., Perrin, M., Pueyo, L., & Savransky, D. (2012, jul). On advanced estimation techniques for exoplanet detection and characterization using ground-based coronagraphs. In Adaptive Optics Systems III, 8447.
• Martinache, F., Guyon, O., Clergeon, C., Garrel, V., & Blain, C. (2012, jul). The Subaru coronagraphic extreme AO project: first observations. In Adaptive Optics Systems III, 8447.
• Mawet, D., Pueyo, L., Lawson, P., Mugnier, L., Traub, W., Boccaletti, A., Trauger, J. T., Gladysz, S., Serabyn, E., Milli, J., Belikov, R., Kasper, M., Baudoz, P., Macintosh, B., Marois, C., Oppenheimer, B., Barrett, H., Beuzit, J., Devaney, N., , Girard, J., et al. (2012, sep). Review of small-angle coronagraphic techniques in the wake of ground-based second-generation adaptive optics systems. In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• McElwain, M. W., Brandt, T. D., Janson, M., Knapp, G. R., Peters, M. A., Burrows, A. S., Carlotti, A., Carr, M. A., Groff, T., Gunn, J. E., Guyon, O., Hayashi, M., Kasdin, N. J., Kuzuhara, M., Lupton, R. H., Martinache, F., Spiegel, D., Takato, N., Tamura, M., , Turner, E. L., et al. (2012, sep). Scientific design of a high contrast integral field spectrograph for the Subaru Telescope. In Ground-based and Airborne Instrumentation for Astronomy IV, 8446.
• Minowa, Y., Hayano, Y., Terada, H., Pyo, T., Oya, S., Hattori, M., Shirahata, M., Takami, H., Guyon, O., Garrel, V., Colley, S., Weber, M., Golota, T., Watanabe, M., Saito, Y., Ito, M., & Iye, M. (2012, jul). Subaru laser guide adaptive optics system: performance and science operation. In Adaptive Optics Systems III, 8447.
• Norris, B. R., Tuthill, P. G., Ireland, M. J., Lacour, S., Zijlstra, A. A., Lykou, F., Evans, T. M., Stewart, P., Bedding, T. R., Guyon, O., & Martinache, F. (2012, jul). Probing dusty circumstellar environments with polarimetric aperture-masking interferometry. In Optical and Infrared Interferometry III, 8445.
• Peters, M. A., Groff, T., Kasdin, N. J., McElwain, M. W., Galvin, M., Carr, M. A., Lupton, R., Gunn, J. E., Knapp, G., Gong, Q., Carlotti, A., Brandt, T., Janson, M., Guyon, O., Martinache, F., Hayashi, M., & Takato, N. (2012, sep). Conceptual design of the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) for the Subaru telescope. In Ground-based and Airborne Instrumentation for Astronomy IV, 8446.
• Schneider, G., Guyon, O., Science Mission, E., & Team, T. (2012, jan). The EXoplanetary Circumstellar Disk Environments and Disk Explorer. In American Astronomical Society Meeting Abstracts #219, 219, #155.13.
• Schneider}, G., Guyon, O., Science, M. E., & Team, {. (2012, jan). The EXoplanetary Circumstellar Disk Environments and Disk Explorer. In American Astronomical Society Meeting Abstracts \#219, 219.
• Tamura, M., Suto, H., Nishikawa, J., Kotani, T., Sato, B., Aoki, W., Usuda, T., Kurokawa, T., Kashiwagi, K., Nishiyama, S., Ikeda, Y., Hall, D., Hodapp, K., Hashimoto, J., Morino, J., Inoue, S., Mizuno, Y., Washizaki, Y., Tanaka, Y., , Suzuki, S., et al. (2012, sep). Infrared Doppler instrument for the Subaru Telescope (IRD). In Ground-based and Airborne Instrumentation for Astronomy IV, 8446.
• Unwin, S., Traub, W., Bryden, G., Brugarolas, P., Chen, P., Guyon, O., Hillenbrand, L., Krist, J., Macintosh, B., Mawet, D., Mennesson, B., Moody, D., Roberts, L. C., Stapelfeldt, K., Stuchlik, D., Trauger, J., & Vasisht, G. (2012, sep). Coronagraphic imaging of debris disks from a high altitude balloon platform. In Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave, 8442.
• Ammons, S. M., Bendek, E. A., & Guyon, O. (2011, oct). Microarcsecond relative astrometry from the ground with a diffractive pupil. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Balasubramanian, K., Cady, E., Pueyo, L., An, X., Shaklan, S., Guyon, O., & Belikov, R. (2011, oct). Diamond turned high precision PIAA optics and four mirror PIAA system for high contrast imaging of exo-planets. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Belikov, R., Pluzhnik, E., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., & Guyon, O. (2011, oct). Laboratory demonstration of high-contrast imaging at inner working angles 2 \ensuremath{\lambda}/D and better. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Belikov, R., Pluzhnik, E., Witteborn, F., Lynch, D., Greene, T., Zell, P., Balasubramanian, K., & Guyon, O. (2011, jan). PIAA Coronagraph Development at NASA Ames: High Contrast Laboratory Demonstration at 2 l/D. In American Astronomical Society Meeting Abstracts \#217, 217.
• Bendek, E. A., Ammons, S. M., Shankar, H., & Guyon, O. (2011, oct). Dynamic distortion calibration using a diffracting pupil: high precision astrometry laboratory demonstration for exoplanet detection. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Blain, C., Guyon, O., Bradley, C., Martinache, F., & Clergeon, C. (2011, sep). An Iterative Model for Micro-Electro-Mechanical-Systems (MEMS) Deformable Mirrors. In Second International Conference on Adaptive Optics for Extremely Large Telescopes. Online at http://ao4elt2.lesia.obspm.fr.
• Cahoy, K. L., Stark, C., Guyon, O., Marley, M., & Fortney, J. (2011, may). Finding the Needle: How To Use A Space-borne Coronagraph To Detect Exoplanets Embedded In Debris Disks. In American Astronomical Society Meeting Abstracts \#218, 218.
• Garrel, V., Guyon, O., Baudoz, P., Martinache, F., Stewart, P., Lozi, J., & Groff, T. (2011, oct). The Subaru coronagraphic extreme AO (SCExAO) system: fast visible imager. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Guyon, O. (2011, jul). High performance coronagraphy for direct imaging of exoplanets. In European Physical Journal Web of Conferences, 16.
• Guyon, O. (2011, sep). Direct imaging of habitable planets with ELTs. In Second International Conference on Adaptive Optics for Extremely Large Telescopes. Online at http://ao4elt2.lesia.obspm.fr.
• Guyon, O., & Martinache, F. (2011, oct). Achieving high-precision ground-based photometry for transiting exoplanets. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Guyon, O., & Walawender, J. (2011, mar). A Low-cost Robotic Imaging Systems for High Precision Photometry. In Telescopes from Afar.
• Guyon, O., Bendek, E., Ammons, M., Shao, M., Shaklan, S., Woodruff, R. A., & Belikov, R. (2011, oct). Diffractive pupil telescope for high precision space astrometry. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Guyon, O., Kern, B., Belikov, R., Shaklan, S., Kuhnert, A., & Give'on, A. (2011, oct). Phase-Induced Amplitude Apodization (PIAA) coronagraphy: recent results and future prospects. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Guyon, O., Martinache, F., Clergeon, C., Russell, R., Groff, T., & Garrel, V. (2011, oct). Wavefront control with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system. In Astronomical Adaptive Optics Systems and Applications IV, 8149.
• Martinache, F., Guyon, O., Garrel, V., Clergeon, C., Groff, T., Stewart, P., Russell, R., & Blain, C. (2011, oct). The Subaru coronagraphic extreme AO project: progress report. In Techniques and Instrumentation for Detection of Exoplanets V, 8151.
• Mateen, M., Guyon, O., & Hart, M. (2011, sep). A sensitivity comparison between the non-linear curvature wavefront sensor and the Shack-Hartmann wavefront sensor in broadband.. In Second International Conference on Adaptive Optics for Extremely Large Telescopes. Online at http://ao4elt2.lesia.obspm.fr.
• Mateen, M., Guyon, O., Sasi{\'an}, J., Garrel, V., & Hart, M. (2011, oct). A non-linear curvature wavefront sensor reconstruction speed and the broadband design. In Astronomical Adaptive Optics Systems and Applications IV, 8149.
• Balasubramanian, K., Shaklan, S. B., Pueyo, L., Wilson, D. W., & Guyon, O. (2010, jul). Low-cost high-precision PIAA optics for high contrast imaging with exo-planet coronagraphs. In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Belikov, R., Pluzhnik, E., Connelley, M. S., Witteborn, F. C., Greene, T. P., Lynch, D. H., Zell, P. T., & Guyon, O. (2010, jul). Laboratory demonstration of high-contrast imaging at 2 \ensuremath{\lambda}/D on a temperature-stabilized testbed in air. In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Belikov, R., Pluzhnik, E., Connelley, M., Greene, T., Lynch, D., McKelvey, M., Witteborn, F., Zell, P., Cahoy, K., & Guyon, O. (2010, jan). Laboratory Demonstration Of High Contrast Imaging At 2 lambda/D With The PIAA Coronagraph. In American Astronomical Society Meeting Abstracts \#215, 215.
• Belikov, R., Pluzhnik, E., Witteborn, F., Greene, T., Lynch, D., Zell, P., & Guyon, O. (2010, oct). Towards direct detection of exo-Earths: high contrast lab demonstration at 2 l/D. In In the Spirit of Lyot 2010.
• Bendek, E., Ammons, T., & Guyon, O. (2010, oct). Single aperture imaging astrometry with a diffracting pupil: laboratory demonstration. In In the Spirit of Lyot 2010.
• Blain, C., Conan, R., Bradley, C., Guyon, O., & Vogel, C. (2010, jan). Characterisation of the influence function non-additivities for a 1024-actuator MEMS deformable mirror. In Adaptative Optics for Extremely Large Telescopes.
• Blain, C., Conan, R., Bradley, C., Guyon, O., Gamroth, D., & Nash, R. (2010, jul). Real-time open-loop control of a 1024-actuator MEMS deformable mirror. In Adaptive Optics Systems II, 7736.
• Enya, K., Kotani, T., Nakagawa, T., Kataza, H., Komatsu, K., Uchida, H., Haze, K., Higuchi, S., Miyata, T., Sako, S., Nakamura, T., Yamashita, T., Narita, N., Tamura, M., Nishikawa, J., Hayano, H., Oya, S., Kokubo, E., Itoh, Y., , Fukagawa, M., et al. (2010, jan). SPICA coronagraph for the detection and characterization of exo-planets. In 38th COSPAR Scientific Assembly, 38.
• Enya, K., Kotani, T., Nakagawa, T., Kataza, H., Komatsu, K., Uchida, H., Haze, K., Higuchi, S., Miyata, T., Sako, S., Nakamura, T., Yamashita, T., Narita, N., Tamura, M., Nishikawa, J., Hayano, H., Oya, S., Kokubo, E., Itoh, Y., , Fukagawa, M., et al. (2010, oct). SPICA Coronagraph. In Pathways Towards Habitable Planets, 430.
• Enya, K., Kotani, T., Nakagawa, T., Matsuhara, H., Kataza, H., Wada, T., Kawada, M., Mita, M., Komatsu, K., Uchida, H., Yamawaki, T., Mitani, S., Sakai, S., Fujiwara, K., Haze, K., Aono, K., Matsuo, T., Yamashita, T., Narita, N., , Nishikawa, J., et al. (2010, oct). Coronagraph with SPICA. In In the Spirit of Lyot 2010.
• Garrel, V., Guyon, O., Baudoz, P., Martinache, F., & Cantalloube, F. (2010, oct). The Subaru coronagraphic extreme AO(SCExAO) system: using new approaches for high contrast imaging on a large telescope. In In the Spirit of Lyot 2010.
• Garrel, V., Guyon, O., Baudoz, P., Martinache, F., Vogt, F., Takashi, Y., Kaito, Y., & Cantalloube, F. (2010, jul). The Subaru coronagraphic extreme AO (SCExAO) system: visible imaging mode. In Adaptive Optics Systems II, 7736.
• Greene, T., Belikov, R., Connelley, M., Guyon, O., Lynch, D., McKelvey, M., Pluzhnik, E., & Witteborn, F. (2010, oct). Testing PIAA Coronagraphs at NASA Ames. In Pathways Towards Habitable Planets, 430.
• Guyon, O. (2010, jan). Ultra high precision wavefront sensing for Extreme-AO on ELTs. In Adaptative Optics for Extremely Large Telescopes.
• Guyon, O., & Shao, M. (2010, jan). A Concept for High Precision Astrometry with a Space Coronagraph. In American Astronomical Society Meeting Abstracts \#215, 215.
• Guyon, O., Martinache, F., Garrel, V., Vogt, F., Yokochi, K., & Yoshikawa, T. (2010, jul). The Subaru coronagraphic extreme AO (SCExAO) system: wavefront control and detection of exoplanets with coherent light modulation in the focal plane. In Adaptive Optics Systems II, 7736.
• Guyon, O., Shaklan, S., Levine, M., Cahoy, K., Tenerelli, D., Belikov, R., & Kern, B. (2010, jul). The pupil mapping exoplanet coronagraphic observer (PECO). In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Guyon, O., Shao, M., Levine, M., Woodruff, R., Ammons, M., Bendek, E., Pitman, J., & Nemati, B. (2010, oct). Exoplanet Detection and Characterization with a Combined Space Astrometry and Coronagraphy Mission. In In the Spirit of Lyot 2010.
• Guyon, O., Shao, M., Shaklan, S., Levine, M., Ammons, M., Bendek, E., Woodruff, R., Nemati, B., & Pitman, J. (2010, jul). Single aperture imaging astrometry with a diffracting pupil: application to exoplanet mass measurement with a small coronagraphic space telescope. In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Guyon}, O., Greene, T., Cahoy, K., Shaklan, S., Tenerelli, D., & Team, {. (2010, oct). The Pupil Mapping Exoplanet Coronagraphic Observer (PECO). In Pathways Towards Habitable Planets, 430.
• Hattori, M., Colley, S., Garrel, V., Egner, S., Golota, T., Guyon, O., Ito, M., Minowa, Y., Oya, S., Saito, Y., Watanabe, M., Hayano, Y., Takami, H., & Iye, M. (2010, jul). Recent development in real-time control system of Subaru adaptive optics including laser guide star mode. In Adaptive Optics Systems II, 7736.
• Ito, M., Hayano, Y., Saito, Y., Takami, H., Iye, M., Hattori, M., Oya, S., Watanabe, M., Akagawa, K., Colley, S., Golota, T., & Guyon, O. (2010, jul). The characteristics of laser-transmission and guide star's brightness for Subaru LGS/AO188 system. In Adaptive Optics Systems II, 7736.
• Martinache, F., & Guyon, O. (2010, oct). The Subaru Coronagraphic Extreme AO Project. In Pathways Towards Habitable Planets, 430.
• Mateen, M., Garrel, V., Hart, M., & Guyon, O. (2010, jul). Results from the laboratory demonstration of the nonlinear curvature wavefront sensor. In Adaptive Optics Systems II, 7736.
• Minowa, Y., Hayano, Y., Oya, S., Watanabe, M., Hattori, M., Guyon, O., Egner, S., Saito, Y., Ito, M., Takami, H., Garrel, V., Colley, S., Golota, T., & Iye, M. (2010, jul). Performance of Subaru adaptive optics system AO188. In Adaptive Optics Systems II, 7736.
• Mueller, U., Stone, J., Peters, B. G., Daniel, J., Greene, T. P., Belikov, R., & Guyon, O. (2010, jul). Narrow ion-beam figuring: a new tool to address extreme slopes on small surfaces located near telescope pupils. In Modern Technologies in Space- and Ground-based Telescopes and Instrumentation, 7739.
• Murakami, N., Guyon, O., Martinache, F., Matsuo, T., Yokochi, K., Nishikawa, J., Tamura, M., Kurokawa, T., Baba, N., Vogt, F., Garrel, V., & Yoshikawa, T. (2010, jul). An eight-octant phase-mask coronagraph for the Subaru coronagraphic extreme AO (SCExAO) system: system design and expected performance. In Ground-based and Airborne Instrumentation for Astronomy III, 7735.
• Oya, S., Hattori, M., Minowa, Y., Negishi, S., Tomono, D., Terada, H., Pyo, T., Watanabe, M., Ito, M., Saito, Y., Egner, S., Hayano, Y., Takami, H., Iye, M., Guyon, O., Garrel, V., Colley, S., & Golota, T. (2010, jul). Tip/tilt offload of Subaru AO188 by telescope secondary mirror. In Adaptive Optics Systems II, 7736.
• Saito, Y., Hayano, Y., Ito, M., Minowa, Y., Egner, S., Oya, S., Watanabe, M., Hattori, M., Garrel, V., Akagawa, K., Guyon, O., Colley, S., Golota, T., Saito, N., Takazawa, A., Ito, M., Takami, H., Wada, S., & Iye, M. (2010, jul). The performance of the laser guide star system for the Subaru Telescope. In Adaptive Optics Systems II, 7736.
• Tenerelli, D., Angel, R., Burge, J., Guyon, O., Zabludoff, A., Belikov, R., Pluzhnik, E., & Egerman, R. (2010, jul). A 4-meter wide field coronagraph space telescope for general astrophysics and exoplanet observations. In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Trauger, J., Stapelfeldt, K., Traub, W., Krist, J., Moody, D., Mawet, D., Serabyn, E., Henry, C., Brugarolas, P., Alexander, J., Gappinger, R., Dawson, O., Mireles, V., Park, P., Pueyo, L., Shaklan, S., Guyon, O., Kasdin, J., Vanderbei, R., , Spergel, D., et al. (2010, jul). ACCESS: a concept study for the direct imaging and spectroscopy of exoplanetary systems. In Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, 7731.
• Trauger, J., Stapelfeldt, K., Traub, W., Krist, J., Moody, D., Serabyn, E., Mawet, D., Pueyo, L., Shaklan, S., Henry, C., Park, P., Gappinger, R., Brugarolas, P., Alexander, J., Mireles, V., Dawson, O., Guyon, O., Kasdin, J., Vanderbei, B., , Spergel, D., et al. (2010, oct). ACCESS: A Concept Study for the Direct Imaging and Spectroscopy of Exoplanetary Systems. In Pathways Towards Habitable Planets, 430.
• Vogt, F., Martinache, F., Guyon, O., Yoshikawa, T., Yokochi, K., Garrel, V., & Matsuo, T. (2010, jul). The Subaru Coronographic Extreme AO (SCExAO) system: implementation and performances of the Coronographic Low Order WaveFront Sensor. In Adaptive Optics Systems II, 7736.
• Watanabe, M., Ito, M., Oya, S., Hayano, Y., Minowa, Y., Hattori, M., Saito, Y., Egner, S., Takami, H., Iye, M., Guyon, O., Garrel, V., Colley, S., & Golota, T. (2010, jul). Visible low-order wavefront sensor for the Subaru LGSAO system. In Adaptive Optics Systems II, 7736.
• Belikov, R., Angel, R., Bekele, A., Cahoy, K., Connelley, M., Dettmann, L., Gavel, D., Give'on, A., Guyon, O., Jay, D., Kasdin, N. J., Kendrick, R., Kern, B., Levine, M., Lynch, D., McKelvey, M., Peters, B., Pluzhnik, E., Shaklan, S., , Shao, M., et al. (2009, mar). Overview of Technology Development for the Phase-Induced Amplitude Apodization (PIAA) Coronagraph. In astro2010: The Astronomy and Astrophysics Decadal Survey, 2010.
• Belikov, R., Connelley, M., Greene, T., Guyon, O., Lynch, D., McKelvey, M., Pluzhnik, E., & Witteborn, F. (2009, jan). Demonstration Of Ohe PIAA Coronagraph For Exoplanet Imaging At NASA Ames.. In American Astronomical Society Meeting Abstracts \#213, 213.
• Belikov, R., Pluzhnik, E., Connelley, M. S., Witteborn, F. C., Lynch, D. H., Cahoy, K. L., Guyon, O., Greene, T. P., & McKelvey, M. E. (2009, aug). First results on a new PIAA coronagraph testbed at NASA Ames. In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Cahoy, K. L., Guyon, O., Marley, M., Belikov, R., & Schneider, G. (2009, sep). Science Performance of the Pupil-mapping Exoplanet Coronagraphic Observer (PECO). In AAS/Division for Planetary Sciences Meeting Abstracts \#41, 41.
• Cahoy, K., Guyon, O., Schneider, G., Marley, M., Belikov, R., Meyer, M., Ridgway, S., Traub, W., & Woolf, N. (2009, aug). Science performance of the Pupil-mapping Exoplanet Coronagraphic Observer (PECO). In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Enya}, K., Kotani, T., Nakagawa, T., Kataza, H., Haze, K., Higuchi, S., Miyata, T., Sako, S., Nakamura, T., Yamashita, T., Narita, N., Tamura, M., Nishikawa, J., Hayano, H., Oya, S., Itoh, Y., Fukagawa, M., Shibai, H., Honda, M., , Baba, N., et al. (2009, dec). SPICA Coronagraph Instrument (SCI) for the Direct Imaging and Spectroscopy of Exo-Planets. In The Next-Generation Infrared Space Mission: SPICA.
• Garrel, V., Guyon, O., Martinache, F., & Egner, S. (2009, aug). Enabling new high contrast imaging science on Subaru Telescope with Electron Multiplying CCDs. In Exoplanets and Disks: Their Formation and Diversity, 1158.
• Greene, T., Cahoy, K., Guyon, O., Kasting, J., Marley, M., Meyer, M., Ridgway, S., Schneider, G., Traub, W., & Woolf, N. (2009, jan). Science Performance of the Pupil-mapping Exoplanet Coronagraphic Observer (PECO). In American Astronomical Society Meeting Abstracts \#213, 213.
• Greene, T., Cahoy, K., Guyon, O., Kasting, J., Marley, M., Ridgway, S., Schneider, G., Traub, W., & Woolf, N. (2009, jan). Discovering and Characterizing the Planetary Systems of Nearby Stars. In astro2010: The Astronomy and Astrophysics Decadal Survey, 2010.
• Guyon, O. (2009, aug). Coronagraphic Techniques for Direct Imaging of Exoplanets and Disks. In Exoplanets and Disks: Their Formation and Diversity, 1158.
• Guyon, O., Angel, J. R., Belikov, R., Egerman, R., Gavel, D., Giveon, A., Greene, T., Cahoy, K., Kern, B., Levine, M., Ridgway, S., Shaklan, S., Tenerelli, D., Vanderbei, R., & Woodruff, R. A. (2009, aug). Detecting and characterizing exoplanets with a 1.4-m space telescope: the Pupil mapping Exoplanet Coronagraphic Observer (PECO). In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Guyon}, O., & Team, {. (2009, dec). Detection and Characterization of Exoplanets and Disks with the 1.4-m Diameter Pupil Mapping Exoplanet Coronagraphic Observer (PECO). In American Astronomical Society Meeting Abstracts \#214, 214.
• Guyon}, O., & Team, {. (2009, jan). Key technologies for the Pupil mapping Exoplanet Coronagraphic Observer (PECO). In American Astronomical Society Meeting Abstracts \#213, 213.
• Kasting, J., Traub, W., Roberge, A., Leger, A., Schwartz, A., Wootten, A., Vosteen, A., Lo, A., Brack, A., Tanner, A., Coustenis, A., Lane, B., Oppenheimer, B., Mennesson, B., Lopez, B., Grillmair, C., Beichman, C., Cockell, C., Hanot, C., , McCarthy, C., et al. (2009, jan). Exoplanet Characterization and the Search for Life. In astro2010: The Astronomy and Astrophysics Decadal Survey, 2010.
• Kern, B., Belikov, R., Give'On, A., Guyon, O., Kuhnert, A., Levine-West, M. B., McMichael, I. C., Moody, D. C., Niessner, A. F., Pueyo, L., Shaklan, S. B., Traub, W. A., & Trauger, J. T. (2009, aug). Phase-induced amplitude apodization (PIAA) coronagraph testing at the High Contrast Imaging Testbed. In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Krist, J. E., Moody, D. C., Mawet, D., Trauger, J. T., Belikov, R., Shaklan, S. B., Guyon, O., & Vanderbei, R. J. (2009, aug). End-to-end simulations of different coronagraphic techniques. In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Levine, B. M., Bairstow, S., Deems, E., Shao, M., Vasisht, G., Zhao, F., Clampin, M., Lyon, R., Guyon, O., Havey, K., Wynn, J., Lane, B., Samuele, R., Vasudevan, G., Woodruff, R., & Tolls, V. (2009, jan). A Mission Study of a Dilute Aperture Visible Nulling Coronagraph Imager (DAViNCI) for the Detection and Spectroscopy of Exo-planets. In American Astronomical Society Meeting Abstracts \#213, 213.
• Martinache, F., & Guyon, O. (2009, aug). The Subaru Coronagraphic Extreme-AO Project. In Techniques and Instrumentation for Detection of Exoplanets IV, 7440.
• Martinache, F., Guyon, O., & Garrel, V. (2009, aug). Aperture Masking Interferometry for Subaru. In Exoplanets and Disks: Their Formation and Diversity, 1158.
• Martinache, F., Guyon, O., Lozi, J., Garrel, V., Blain, C., & Sivo, G. (2009, aug). The Subaru Coronagraphic Extreme AO Project. In Exoplanets and Disks: Their Formation and Diversity, 1158.
• Martinache, F., Guyon, O., Lozi, J., Tamura, M., Hodapp, K., Suzuki, R., Hayano, Y., & McElwain, M. (2009, jan). The Subaru Coronagraphic Extreme AO Project. In American Astronomical Society Meeting Abstracts \#213, 213.
• Mountain, M., Marel, R., Soummer, R., Koekemoer, A., Ferguson, H., Postman, M., Gavel, D. T., Guyon, O., Simons, D., & Traub, W. A. (2009, mar). Comparison of optical observational capabilities for the coming decades: ground versus space. In astro2010: The Astronomy and Astrophysics Decadal Survey, 2010.
• Shao, M., Bairstow, S., Deems, E., Fletcher, L., Levine, B. M., Orton, G., Vasisht, G., Zhao, F., Clampin, M., Lyon, R. G., Guyon, O., Lane, B. F., Havey, K., Wynn, J., Samuele, R., Vasudevan, G., Woodruff, R. A., Tolls, V., Malbet, F., & Leger, A. (2009, jan). Direct Detection and Spectroscopy of Exo-Earths; The Need for High Angular Resolution and Other Observational Requirements. In astro2010: The Astronomy and Astrophysics Decadal Survey, 2010.
• Shao, M., Bairstow, S., Deems, E., Fletcher, L., Levine, B., Orton, G., Vasisht, G., Wayne, L., Zhao, F., Clampin, M., Lyon, R., Guyon, O., Lane, B., Havey, K., Wynn, J., Samuele, R., Vasudevan, G., Woodruff, R., Tolls, V., , Malbet, F., et al. (2009, dec). A Mission Concept Study of a Dilute Aperture Visible Nulling Coronagraph Imager (DAViNCI) for the Detection and Spectroscopy of Exo-planets. In American Astronomical Society Meeting Abstracts \#214, 214.
• Spergel, D. N., Kasdin, J., Belikov, R., Atcheson, P., Beasley, M., Calzetti, D., Cameron, B., Copi, C., Desch, S., Dressler, A., Ebbets, D., Egerman, R., Fullerton, A., Gallagher, J., Green, J., Guyon, O., Heap, S., Jansen, R., Jenkins, E., , Kasting, J., et al. (2009, jan). THEIA: Telescope for Habitable Exoplanets and Interstellar/Intergalactic Astronomy. In American Astronomical Society Meeting Abstracts \#213, 213.
• Suzuki, R., Tamura, M., Suto, H., Morino, J., Hashimoto, J., Kudo, T., Kandori, R., Murakami, N., Nishikawa, J., Ukita, N., Takami, H., Guyon, O., Nishimura, T., Hayashi, M., Izumiura, H., Abe, L., Tavrov, A., Jacobson, S., Stahlberger, V., , Yamada, H., et al. (2009, aug). HiCIAO: A High-contrast Instrument for the Next Generation Subaru Adaptive Optics. In Exoplanets and Disks: Their Formation and Diversity, 1158.
• Trauger, J. T., Stapelfeldt, K., Traub, W., Krist, J., Moody, D., Serabyn, E., Mawet, D., Park, P., Henry, C., Gappinger, R., Brugarolas, P., Dawson, O., Shaklan, S., Pueyo, L., Guyon, O., Kasdin, J., Spergel, D., Vanderbei, R., Marcy, G., , Brown, R., et al. (2009, jan). ACCESS -- A Science and Engineering Assessment of Space Coronagraph Concepts for the Direct Imaging and Spectroscopy of Exoplanetary Systems. In American Astronomical Society Meeting Abstracts \#213, 213.
• Blain, C., Guyon, O., Conan, R., & Bradley, C. (2008, jul). Simple iterative method for open-loop control of MEMS deformable mirrors. In Adaptive Optics Systems, 7015.
• Enya, K., Abe, L., Haze, K., Tanaka, S., Nakagawa, T., Kataza, H., Higuchi, S., Miyata, T., Sako, S., Nakamura, T., Tamura, M., Nishikawa, J., Murakami, N., Itoh, Y., Wakayama, T., Sato, T., Nakagiri, N., Guyon, O., Venet, M., & Bierden, P. (2008, jul). Mid-infrared coronagraph for SPICA. In Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter, 7010.
• Guyon, O. (2008, jul). Ultra-high-sensitivity wavefront sensing for extreme-AO. In Adaptive Optics Systems, 7015.
• Guyon, O., Angel, J. R., Backman, D., Belikov, R., Gavel, D., Giveon, A., Greene, T., Kasdin, J., Kasting, J., Levine, M., Marley, M., Meyer, M., Schneider, G., Serabyn, G., Shaklan, S., Shao, M., Tamura, M., Tenerelli, D., Traub, W., , Trauger, J., et al. (2008, jul). Pupil mapping Exoplanet Coronagraphic Observer (PECO). In Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter, 7010.
• Hayano, Y., Takami, H., Guyon, O., Oya, S., Hattori, M., Saito, Y., Watanabe, M., Murakami, N., Minowa, Y., Ito, M., Colley, S., Eldred, M., Golota, T., Dinkins, M., Kashikawa, N., & Iye, M. (2008, jul). Current status of the laser guide star adaptive optics system for Subaru Telescope. In Adaptive Optics Systems, 7015.
• Hodapp, K. W., Suzuki, R., Tamura, M., Abe, L., Suto, H., Kandori, R., Morino, J., Nishimura, T., Takami, H., Guyon, O., Jacobson, S., Stahlberger, V., Yamada, H., Shelton, R., Hashimoto, J., Tavrov, A., Nishikawa, J., Ukita, N., Izumiura, H., , Hayashi, M., et al. (2008, jul). HiCIAO: the Subaru Telescope's new high-contrast coronographic imager for adaptive optics. In Ground-based and Airborne Instrumentation for Astronomy II, 7014.
• Minowa, Y., Takami, H., Watanabe, M., Hayano, Y., Miyake, M., Iye, M., Oya, S., Hattori, M., Murakami, N., Guyon, O., Saito, Y., Itoh, M., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2008, jul). Development of a dichroic beam splitter for Subaru AO188. In Adaptive Optics Systems, 7015.
• Oya, S., Minowa, Y., Hattori, M., Watanabe, M., Hayano, Y., Itoh, M., Saito, Y., Takami, H., Iye, M., Guyon, O., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2008, jul). Characterization of vibrating shape of a bimorph deformable mirror. In Adaptive Optics Systems, 7015.
• Shao, M., Bairstow, S., Martin Levine, B., Vasisht, G., Lane, B. F., Vasudevan, G., Woodruff, R., Samuele, R., Wynn, J., Clampin, M., Lyon, R., & Guyon, O. (2008, jul). DAVINCI, a diluter aperture visible nulling coronagraphic instrument. In Optical and Infrared Interferometry, 7013.
• Trauger, J., Stapelfeldt, K., Traub, W., Henry, C., Krist, J., Mawet, D., Moody, D., Park, P., Pueyo, L., Serabyn, E., Shaklan, S., Guyon, O., Kasdin, J., Spergel, D., Vanderbei, R., Belikov, R., Marcy, G., Brown, R. A., Schneider, J., , Woodgate, B., et al. (2008, jul). ACCESS: a NASA mission concept study of an Actively Corrected Coronagraph for Exoplanet System Studies. In Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter, 7010.
• Watanabe, M., Oya, S., Hayano, Y., Takami, H., Hattori, M., Minowa, Y., Saito, Y., Ito, M., Murakami, N., Iye, M., Guyon, O., Colley, S., Eldred, M., Golota, T., & Dinkins, M. (2008, jul). Implementation of 188-element curvature-based wavefront sensor and calibration source unit for the Subaru LGSAO system. In Adaptive Optics Systems, 7015.
• Abe, L., Guyon, O., Tamura, M., Enya, K., Tanaka, S., & Matsuo, T. (2007, jun). Status of PIAA-related Experiments and Projects. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Angel, J., Kang, T., Cuerden, B., Stahl, P., & Guyon, O. (2007, may). Thermally Actuated Primary Mirror for Space Exoplanet Imaging. In American Astronomical Society Meeting Abstracts \#210, 210.
• Angel, R., Kang, T., Cuerden, B., Guyon, O., & Stahl, P. (2007, sep). Active thermal figure control for the TOPS II primary mirror. In Techniques and Instrumentation for Detection of Exoplanets III, 6693.
• Angel, R., Kang, T., Cuerden, B., Stahl, P., Guyon, O., & Tenerelli, D. (2007, jun). Thermally Actuated Primary Mirror for Space Exoplanet Imaging with TOPS. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Enya, K., Abe, L., Tanaka, S., Haze, K., Venet, M., Nakagawa, T., Kataza, H., Tamura, M., Nishikawa, J., Murakami, N., Fujita, K., Itoh, Y., Guyon, O., Pluzhnik, E., Wakayama, T., Sato, T., & Nakagiri, N. (2007, sep). Coronagraph project with the SPICA mission. In Techniques and Instrumentation for Detection of Exoplanets III, 6693.
• Enya}, K., Abe, L., Tanaka, S., Nakagawa, T., Tamura, M., Kataza, H., Guyon, O., & Group, {. W. (2007, jun). The SPICA Coronagraph Project. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Guyon, O. (2007, jan). Focal Plane and Non-linear Curvature Wavefront Sensing for High Contrast Coronagraphic Adaptive Optics Imaging. In Advanced Maui Optical and Space Surveillance Technologies Conference.
• Guyon, O. (2007, jun). The Coronagraph Tree of Life. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Guyon, O. (2007, may). Tops. In Small- and Mid-Scale Exoplanet Space Missions.
• Guyon, O. (2007, sep). High-performance curvature wavefront sensing for extreme AO. In Astronomical Adaptive Optics Systems and Applications III, 6691.
• Guyon, O., Angel, J. R., Bowers, C., Burge, J., Burrows, A., Codona, J., Greene, T., Iye, M., Kasting, J., Martin, H., McCarthy Jr., ., Meadows, V., Meyer, M., Pluzhnik, E. A., Sleep, N., Tamura, M., Tenerelli, D., Vanderbei, R., Woodgate, B., , Woodruff, R. A., et al. (2007, sep). TOPS: a small space telescope using phase induced-amplitude apodization (PIAA) to image rocky and giant exo-planets. In Techniques and Instrumentation for Detection of Exoplanets III, 6693.
• Guyon, O., Angel, J., Bowers, C., Burge, J., Burrows, A., Codona, J., Greene, T., Iye, M., Kasting, J., Martin, H., McCarthy, D., Meadows, V., Meyer, M., Pluzhnik, E., Sleep, N., Spears, T., Tamura, M., Tenerelli, D., Vanderbei, R., , Woodgate, B., et al. (2007, jun). Direct Imaging of Nearby Exoplanets with a Small Size Space Telescope: Telescope to Observe Planetary System (TOPS). In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Guyon, O., Angel, R., Bowers, C., Burge, J., Burrows, A., Codona, J., Greene, T., Iye, M., Kasting, J., Martin, H., McCarthy, D., Meadows, V., Meyer, M., Pluzhnik, E., Sleep, N., Spears, A., Tamura, M., Tenerelli, D., Vanderbei, R., , Woodgate, B., et al. (2007, may). Direct Imaging Of Nearby Exoplanets With A Small Size Space Telescope: Telescope To Observe Planetary System (TOPS). In American Astronomical Society Meeting Abstracts \#210, 210.
• Hodapp, K., Tamura, M., Suzuki, R., Jacobson, S., Stahlberger, V., Yamada, H., Takami, H., Guyon, O., Hashimoto, J., & Abe, L. (2007, may). HiCIAO - Subaru's New High-contrast Coronographic Imager For Adaptive Optics. In American Astronomical Society Meeting Abstracts \#210, 210.
• Shaklan, S. B., Give'on, A., Belikov, R., Pueyo, L., & Guyon, O. (2007, sep). Broadband wavefront control in a pupil mapping coronagraph. In Techniques and Instrumentation for Detection of Exoplanets III, 6693.
• Takami, H., Hayano, Y., Oya, S., Hattori, M., Watanabe, M., Guyon, O., Eldred, M., Colley, S., Saito, Y., Itoh, M., & Dinkins, M. (2007, jan). The First Light of the Subaru Laser Guide Star Adaptive Optics System. In Advanced Maui Optical and Space Surveillance Technologies Conference.
• Tamura, M., Hodapp, K., Suzuki, R., Abe, L., Takami, H., Suto, H., Guyon, O., Kandori, R., Morino, J., Hashimoto, J., Stahlberger, V., Jacobson, S., Yamada, H., Shelton, R., Tavrov, A., Murakami, N., Nishikawa, J., Hayashi, M., Usuda, T., , Yamada, T., et al. (2007, jun). HiCIAO and Exoplanet/Disk Searches on Subaru. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Tanaka, S., Guyon, O., Pluzhnik, E., Abe, L., Enya, K., & Nakagawa, T. (2007, jun). Laboratory Demonstration of the PIAA/Binary-Mask Hybrid Coronagraph. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Totems, J., & Guyon, O. (2007, jun). High Contrast Tests with a PIAA Coronagraph in Air. In In the Spirit of Bernard Lyot: The Direct Detection of Planets and Circumstellar Disks in the 21st Century.
• Guyon, O. (2006, jan). High Contrast Adaptive Optics for Exoplanet Detections: performance limits and optimal wavefront sensing strategy. In IAU Colloq. 200: Direct Imaging of Exoplanets: Science \& Techniques.
• Guyon, O., Angel, J. R., Bowers, C., Burge, J., Burrows, A., Codona, J., Greene, T., Iye, M., Kasting, J., Martin, H., McCarthy Jr., ., Meadows, V., Meyer, M., Pluzhnik, E. A., Sleep, N., Spears, T., Tamura, M., Tenerelli, D., Vanderbei, R., , Woodgate, B., et al. (2006, jun). Telescope to Observe Planetary Systems (TOPS): a high throughput 1.2-m visible telescope with a small inner working angle. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6265.
• Guyon, O., Angel, J., Bowers, C., Burge, J., Burrows, A., Codona, J., Greene, T., Iye, M., Kasting, J., Martin, H., McCarthy, D., Meadows, V., Meyer, M., Pluzhnik, E., Sleep, N., Spears, T., Tamura, M., Tenerelli, D., Vanderbei, R., , Woodgate, B., et al. (2006, dec). Telescope to Observe Planetary Systems (TOPS): A High Efficiency Coronagraphic 1.2-m Visible Telescope. In American Astronomical Society Meeting Abstracts, 209.
• Guyon, O., Gallet, B., Pluzhnik, E. A., Takami, H., & Tamura, M. (2006, jun). High contrast imaging with focal plane wavefront sensing for ground based telescopes. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6272.
• Guyon, O., Pluzhnik, E. A., Ridgway, S., & Woodruff, R. A. (2006, jun). Imaging extrasolar terrestrial planets from space with a PIAA coronagraph. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6265.
• Hayano, Y., Saito, Y., Ito, M., Saito, N., Kato, M., Akagawa, K., Takazawa, A., Colley, S. A., Dinkins, M. C., Eldred, M., Golota, T. I., Guyon, O., Hattori, M., Oya, S., Watanabe, M., Takami, H., Wada, S., & Iye, M. (2006, jun). The laser guide star facility for Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6272.
• Hodapp, K. W., Tamura, M., Suzuki, R., Jacobson, S., Stahlberger, V., Yamada, H., Takami, H., Guyon, O., & Abe, L. (2006, jun). Design of the HiCIAO instrument for the Subaru Telescope. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6269.
• Ito, M., Hayano, Y., Saito, N., Akagawa, K., Kato, M., Saito, Y., Takazawa, A., Takami, H., Iye, M., Wada, S., Colley, S. A., Dinkins, M. C., Eldred, M., Golota, T. I., Guyon, O., Hattori, M., Oya, S., & Watanabe, M. (2006, jun). Transmission characteristics of high-power 589-nm laser beam in photonic crystal fiber. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6272.
• Martinache, F., & Guyon, O. (2006, jan). Performance of a Phase Induced Amplitude Apodization Coronograph. In EAS Publications Series, 22.
• Oya, S., Bouvier, A., Guyon, O., Watanabe, M., Hayano, Y., Takami, H., Iye, M., Hattori, M., Saito, Y., Itoh, M., Colley, S., Dinkins, M., Eldred, M., & Golota, T. (2006, jun). Performance of the deformable mirror for Subaru LGSAO. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6272.
• Pluzhnik, E. A., Guyon, O., Ridgway, S., Woodruff, R., Blain, C., Martinache, F., & Galicher, R. (2006, jan). The Phase Induced Amplitude Apodization Coronagraph: an overview of simulations and laboratory effort.. In IAU Colloq. 200: Direct Imaging of Exoplanets: Science \& Techniques.
• Pluzhnik, E., Guyon, O., Colley, S., Gallet, B., Ridgway, S., Woodruff, R., Tanaka, S., & Warren, M. (2006, dec). The PIAA Coronagraph Prototype: First Laboratory Results.. In American Astronomical Society Meeting Abstracts, 209.
• Pluzhnik, E., Guyon, O., Ridgway, S., Woodruff, R., & Gallet, B. (2006, sep). PIAA Coronagraph: the Method Overview. In American Astronomical Society Meeting Abstracts \#208, 208.
• Pluzhnik, E., Guyon, O., Warren, M., Ridgway, S. T., & Woodruff, R. A. (2006, jun). PIAA coronagraph design: system optimization and first optics testing. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6265.
• Takami, H., Colley, S., Dinkins, M., Eldred, M., Guyon, O., Golota, T., Hattori, M., Hayano, Y., Ito, M., Iye, M., Oya, S., Saito, Y., & Watanabe, M. (2006, jun). Status of Subaru laser guide star AO system. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6272.
• Tamura, M., Hodapp, K., Takami, H., Abe, L., Suto, H., Guyon, O., Jacobson, S., Kandori, R., Morino, J., Murakami, N., Stahlberger, V., Suzuki, R., Tavrov, A., Yamada, H., Nishikawa, J., Ukita, N., Hashimoto, J., Izumiura, H., Hayashi, M., , Nakajima, T., et al. (2006, jun). Concept and science of HiCIAO: high contrast instrument for the Subaru next generation adaptive optics. In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 6269.
• Tanaka, S., Guyon, O., & Pluzhnik, E. (2006, dec). Design and Lab Demonstration of the PIAA/Binary-Mask Hybrid Coronagraph. In American Astronomical Society Meeting Abstracts, 209.
• Guyon, O., Pluzhnik, E., Woodruff, R., Ridgway, S., Galicher, R., Martinache, F., & Blain, C. (2005, dec). The PIAA Coronagraph: an Efficient Coronagraph for Direct Imaging of Extrasolar Planets from Space. In American Astronomical Society Meeting Abstracts, 207.
• Guyon, O., Sanders, D., & Stockton, A. (2005, jan). A Near-Infrared Adaptive Optics Imaging Survey of Nearby QSOs. In Science with Adaptive Optics.
• Pluzhnik, E., Guyon, O., Ridgway, S., Martinache, F., Woodruff, R., Blain, C., & Galicher, R. (2005, dec). The PIAA Coronagraph: Optical design and Diffraction Effects. In American Astronomical Society Meeting Abstracts, 207.
• Roth, K., Baker, A., Edmunds, M., & Guyon, O. (2005, jan). Using AO to Identify Damped Lyman \ensuremath{\alpha} Absorption Systems at Redshift z \ensuremath{\sim} 2. In Science with Adaptive Optics.
• Guyon, O. (2004, jan). Coronagraphy vs. Nulling. In EAS Publications Series, 12.
• Guyon, O. (2004, jan). Pupil Remapping Techniques for High Dynamical Range Imaging. In EAS Publications Series, 12.
• Guyon, O. (2004, oct). Synchronous interferometric speckle subtraction (SISS): a concept to remove speckle noise in adaptive optics imaging and interferometry. In Advancements in Adaptive Optics, 5490.
• Guyon, O., Arimoto, N., Blain, C., Colley, S., Eldred, M., Goto, M., Hattori, M., Hayano, Y., Iye, M., Kamata, Y., Kane, T., Kobayashi, N., Watanabe, M., Minowa, Y., Oya, S., Saito, Y., Takami, H., & Takato, N. (2004, oct). Subaru Telescope LGSAO: overview of expected performance. In Advancements in Adaptive Optics, 5490.
• Guyon, O., Ridgway, S., Aime, C., Boccaletti, A., Beuzit, J., Galicher, R., Kern, P., Kotani, T., Lagrange, A., Lyon, R. G., Malbet, F., Murakawa, K., Otsubo, M., Rouan, D., Soummer, R., Suto, H., Tamura, M., & Woodruff, R. A. (2004, oct). Pupil Remapping Coronagraph (PRC): a high-performance coronagraph for a small-size visible Terrestrial Planet Finder. In Optical, Infrared, and Millimeter Space Telescopes, 5487.
• Hayano, Y., Saito, Y., Saito, N., Akagawa, K., Kamata, Y., Kanzawa, T., Kurakami, T., Takato, N., Colley, S., Eldred, M., Kane, T., Guyon, O., Oya, S., Watanabe, M., Hattori, M., Golota, T., Dinkins, M., Kobayashi, N., Minowa, Y., , Goto, M., et al. (2004, oct). Design of laser system for Subaru LGS AO. In Advancements in Adaptive Optics, 5490.
• Iye, M., Takami, H., Takato, N., Oya, S., Hayano, Y., Guyon, O., Colley, S. A., Hattori, M., Watanabe, M., Eldred, M., Saito, Y., Saito, N., Akagawa, K., & Wada, S. (2004, dec). Cassegrain and Nasmyth adaptive optics systems of 8.2-m Subaru telescope. In Adaptive Optics and Applications III, 5639.
• Martinache, F., Guyon, O., Pluzhnik, E., Ridgway, S., & Galicher, R. (2004, dec). The Phase-Induced Amplitude Apodization Coronagraph (PIAAC): Performance for Imaging of Earth-like Exoplanets.. In American Astronomical Society Meeting Abstracts, 205.
• Oya, S., Guyon, O., Watanabe, M., Hayano, Y., Takami, H., Iye, M., Arimoto, N., Colley, S., Eldred, M., Kane, T., Hattori, M., Saito, Y., Kamata, Y., Kobayashi, N., Minowa, Y., Goto, M., & Takato, N. (2004, oct). Deformable mirror design of Subaru LGSAO system. In Advancements in Adaptive Optics, 5490.
• Perrin, G. S., Lai, O., Woillez, J. M., Guerin, J., Kotani, T., Vergnole, S., Adamson, A. J., Ftaclas, C., Guyon, O., Lena, P. J., Nishikawa, J., Reynaud, F., Roth, K. C., Ridgway, S. T., Tokunaga, A. T., & Wizinowich, P. L. (2004, oct). 'ohana. In New Frontiers in Stellar Interferometry, 5491.
• Pluzhnik, E., Guyon, O., Galicher, R., Ridgway, S., & Martinache, F. (2004, dec). The Phase-Induced Amplitude Apodization Coronagraph (PIAAC): Results of Numerical Simulations and Laboratory Experiments. In American Astronomical Society Meeting Abstracts, 205.
• Sanders, D., Ishida, C., Mazzarella, J., Veilleux, S., Surace, J., Guyon, O., Jensen, J., & Kim, D. -. (2004, nov). The infrared universe: The cosmic evolution of superstarbursts and massive black holes. In The Interplay Among Black Holes, Stars and ISM in Galactic Nuclei, 222.
• Watanabe, M., Takami, H., Takato, N., Colley, S., Eldred, M., Kane, T., Guyon, O., Hattori, M., Goto, M., Iye, M., Hayano, Y., Kamata, Y., Arimoto, N., Kobayashi, N., & Minowa, Y. (2004, oct). Design of the Subaru laser guide star adaptive optics module. In Advancements in Adaptive Optics, 5490.
• Guyon, O. (2003, feb). Field of view of fiber interferometers and applications to OHANA. In Interferometry for Optical Astronomy II, 4838.
• Guyon, O. (2003, feb). Wide field nulling imager for TPF: the Boeing-SVS hypertelescope concept. In Interferometry in Space, 4852.
• Guyon, O. (2003, jan). A Wide Field Nulling Imager for Direct Terrestrial Exoplanets Detection. In EAS Publications Series, 8.
• Guyon, O., Ridgway, S., & Otsubo, M. (2003, oct). Phase-induced pupil apodization: a new concept for a simplier DARWIN/TPF. In Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets, 539.
• Guyon}, O., Ridgway, S., & Collaboration, {. (2003, dec). Pupil Remapping Apodization: a 2m Terrestrial Planet Finder ?. In American Astronomical Society Meeting Abstracts, 203.
• Lai, O., Ridgway, S. T., Berger, J., Dougados, C., Foresto}, V., Guyon, O., Lachaume, R., Magnier, E., Malbet, F., Menard, F., Mourard, D., Perrin, G. S., Sol, H., Warren, S., & Woillez, J. (2003, feb). OHANA: representative science objectives. In Interferometry for Optical Astronomy II, 4838.
• Perrin, G. S., Lai, O., Woillez, J., Guerin, J., Reynaud, F., Ridgway, S. T., Lena, P. J., Wizinowich, P. L., Tokunaga, A. T., Nishikawa, J., Rigaut, F. J., Adamson, A. J., & Guyon, O. (2003, feb). OHANA phase II: a prototype demonstrator of fiber linked interferometry between very large telescopes. In Interferometry for Optical Astronomy II, 4838.
• Woillez, J., Sol, H., Lai, O., Guyon, O., & Perrin, G. (2003, feb). Extragalactic astronomy with the OHANA array. In Interferometry for Optical Astronomy II, 4838.
• Guyon, O., Sanders, D., Stockton, A., Baudoz, P., & Potter, D. (2001, may). Adaptive optics imaging of QSO host galaxies with Hokupa'a on the Gemini North telescope. In American Astronomical Society Meeting Abstracts \#198, 198.
• Potter, D., Baudoz, P., Guyon, O., Brandner, W., Close, L., Graves, J., & Northcott, M. (2001, may). A High Dynamic Range Dual Imaging Polarimetric Survey of Circumstellar Disks around Young Stars using Gemini North with Hokupa`a. In American Astronomical Society Meeting Abstracts \#198, 198.
• Roth, K., Guyon, O., Chun, M., Jensen, J., Jorgensen, I., Rigaut, F., & Walther, D. (2001, may). Hokupa'a Performance and Point Spread Function Characterization. In American Astronomical Society Meeting Abstracts \#198, 198.
• Baudoz, P., Roddier, F., Roddier, C., Guyon, O., Potter, D., Brandner, W., Gay, J., Rabbia, Y., & Close, L. (2000, dec). Substellar mass companion search with adaptive optics at University of Hawaii. In American Astronomical Society Meeting Abstracts, 197.
• Boeker, T., Allen, R. J., Rajagopal, J., & Guyon, O. (2000, jul). Simulating instrumental phase errors for SIM. In Interferometry in Optical Astronomy, 4006.
• Brandner, W., Stolte, A., Grebel, E. K., Brandl, B., Iwamuro, F., Maihara, T., Motohara, K., Baudoz, P., Graves, B., Guyon, O., Northcott, M., & Potter, D. (2000, dec). A NIR high-resolution study of Galactic Starburst Clusters. In American Astronomical Society Meeting Abstracts, 197.
• Guyon, O., & Roddier, F. (2000, jan). Nulling Stellar Coronagraphic Imaging Using Space Interferometric Arrays. In Darwin and Astronomy : the Infrared Space Interferometer, 451.
• Guyon, O., & Roddier, F. J. (2000, jul). Direct exoplanet imaging possibilities of the nulling stellar coronagraph. In Interferometry in Optical Astronomy, 4006.
• Guyon, O., Sanders, D., Roddier, C., Roddier, F., Brandner, W., Baudoz, P., & Potter, D. (2000, dec). QSO hosts imaging capabilities of Hokupa'a on the Gemini North telescope. In American Astronomical Society Meeting Abstracts, 197.
• Potter, D., Baudoz, P., Brandner, W., Close, L., Graves, B., Guyon, O., & Northcott, M. (2000, dec). Gemini/Hokupa`a Adaptive Optics Observations of Circumstellar Disks. In American Astronomical Society Meeting Abstracts, 197.
• Guyon, O., & Roddier, F. (1999, jan). The nulling coronagraph applied to interferometric arrays. In Working on the Fringe: Optical and IR Interferometry from Ground and Space, 194.
• Guyon, O., Rajagopal, J., & Allen, R. (1999, dec). Imaging with SIM - Instrument errors and image quality. In American Astronomical Society Meeting Abstracts, 195.
• Guyon, O., Roddier, C., Elon Graves, J., Roddier, F., Cuevas, S., Espejo, C., Martinez, A., Gonzales, S., Bisiacchi, G., & Vuntersmeri, V. (1999, jan). The Nulling Coronograph. In European Southern Observatory Conference and Workshop Proceedings, 56.
• Roddier, F., Roddier, C., Close, L., Dumas, C., Graves, J., Guyon, O., Han, B., Northcott, M., Owen, T., Tholen, D., & Brahic, A. (1999, jan). Planetary Science with Adaptive Optics: Results from the UH AO Systems. In European Southern Observatory Conference and Workshop Proceedings, 56.

Case Studies

• Schneider, G., Lozi, J., Guyon, O., Newman, K. P., Belikov, R., Lynch, D., Zell, P., Thomas, S., Pluzhnik, E., Witteborn, F., Bendek, E., Hix, T., & Nordt, A. (2015. EXCEDE Technology Milestone #2: Broadband Contrast Demonstration(pp 1 - 29).
• Schneider, G., Lozi, J., Guyon, O., Newman, K., Belikov, R., Sirbu, D., Lynch, D., Zell, P., Thomas, S., Pluzhnik, E., Witteborn, F., Bendek, E., Hix, T., Nort, A., Schneider, G., Lozi, J., Guyon, O., Newman, K., Belikov, R., , Sirbu, D., et al. (2015. EXCEDE Technology Milestone #2: Broadband Contrast Demonstration Final Report(pp 1 - 45).

Others

• Bendek, E., Belikov, R., Guyon, O., Greene, T., Pluzhnik, E., Milster, T., Rodack, A., Finan, E., & Knight, J. (2017). Technology Development for Exoplanet Missions - Technology Milestone Report.
• Guyon, O. (2017). Integrating Advanced Wavefront Control and Image Processing for High Contrast Imaging.
• Ammons, S. M., Marois, C., Macintosh, B., Konopacky, Q., Neichel, B., Galicher, R., Bendek, E., & Guyon, O. (2014). A Test of GEMS Astrometric Precision for Exoplanet Detection and Mass Measurement.
• Ammons, S. M., Marois, C., Macintosh, B., Konopacky, Q., Neichel, B., Galicher, R., Bendek, E., & Guyon, O. (2013). A Test of GEMS Astrometric Precision for Exoplanet Detection and Mass Measurement.
• Guyon, O. (2009). Imaging of beta Pictoris disk and Planet(s).
• Guyon, O. (2008). High Resolution Imaging of Beta Pictoris disk's inner region.
• Veilleux, S., Barnes, J., Contursi, A., Dasyra, K., Genzel, R., Guyon, O., Joseph, R., Lehnert, M., Lord, S., Lutz, D., Mazzarella, J., Mihos, C., Netzer, H., Sanders, D., Sternberg, A., Stockton, A., Sturm, E., & Tacconi, L. (2004). The Evolution of Activity in Massive Gas-Rich Mergers.