Andras Gaspar

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• Beichman, C., Bryden, G., Llop-Sayson, J., Ygouf, M., Greenbaum, A., Leisenring, J., Gaspar, A., Krist, J., Rieke, G., Wolff, S., Su, K., Hodapp, K., Meyer, M., Kelly, D., Boyer, M., Johnstone, D., Horner, S., & Rieke, M. (2025). Searching for Planets Orbiting Vega with the James Webb Space Telescope. Astronomical Journal, 169(Issue 1). doi:10.3847/1538-3881/ad890d
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  The most prominent of the IRAS debris disk systems, α Lyrae (Vega), at a distance of 7.7 pc, has been observed by both the NIRCam and MIRI instruments on the James Webb Space Telescope. This paper describes NIRCam coronagraphic observations, which have achieved F444W contrast levels of 3 × 10−7 at 1″ (7.7 au), 1 × 10−7 at 2″ (15 au), and a few × 10−8 beyond 5″ (38 au), corresponding to masses of
• Gordon, K. D., Sloan, G. C., Marin, M. G., Libralato, M., Rieke, G., Aguilar, J. A., Bohlin, R., Cracraft, M., Decleir, M., Gaspar, A., Kendrew, S., Law, D. R., Noriega-Crespo, A., & Regan, M. (2025). The James Webb Space Telescope Absolute Flux Calibration. II. Mid-infrared Instrument Imaging and Coronagraphy. Astronomical Journal, 169(Issue 1). doi:10.3847/1538-3881/ad8cd4
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  The absolute flux calibration of the Mid-Infrared Instrument imaging and coronagraphy is based on observations of multiple stars taken during the first 2.5 yr of James Webb Space Telescope operations. The observations were designed to ensure that the flux calibration is valid for a range of flux densities, different subarrays, and different types of stars. The flux calibration was measured by combining observed aperture photometry corrected to infinite aperture with predictions based on previous observations and models of stellar atmospheres. A subset of these observations was combined with model point-spread functions to measure the corrections to infinite aperture. Variations in the calibration factor with time, flux density, background level, type of star, subarray, integration time, rate, and well depth were investigated, and the only significant variations were with time and subarray. Observations of the same star taken approximately every month revealed a modest time-dependent response loss seen mainly at the longest wavelengths. This loss is well characterized by a decaying exponential with a time constant of ∼200 days. After correcting for the response loss, the band-dependent scatter around the corrected average (i.e., repeatability) was found to range from 0.1% to 1.2%. Signals in observations taken with different subarrays can be lower by up to 3.4% compared to FULL frame. After correcting for the time and subarray dependencies, the scatter in the calibration factors measured for individual stars ranges from 1% to 4% depending on the band. The formal uncertainties on the flux calibration averaged for all observations are 0.3%-1.0%, with longer-wavelength bands generally having larger uncertainties.
• Llop-Sayson, J., Beichman, C., Bryden, G., Ygouf, M., Gaspar, A., Thompson, W., Sanghi, A., Mawet, D., Meshkat, T., Greenbaum, A. Z., Leisenring, J., Wolff, S., Rieke, M., & Rieke, G. (2025). Searching for Planets Orbiting ϵ Eridani with JWST/NIRCam. Astronomical Journal, 170(Issue 4). doi:10.3847/1538-3881/adf727
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  We present observations of ϵ Eridani with the JWST/NIRCam coronagraph aimed at imaging planets orbiting within this system. In particular, these observations targeted (1) the Jupiter-like planet, first detected orbiting at 3.5 au with radial velocity observations, and (2) the planet postulated to be responsible for carving the edges of ϵ Eridani’s outer ring, expected to orbit at 40-50 au. However, no point sources were detected at a statistically significant level. We report new, improved upper limits at 4 μm: ∼1 × 10−6 contrast at 1″, and ∼2 × 10−8 beyond 5″. The latter contrast limit precludes Saturn-mass planets at separations >16 au given current models. We also report upper limits for ϵ Eridani’s disk emission at 4 μm. While the radial surface brightness profile shows no evidence of emission, we detect a 1σ surface brightness signal on the east side of the system, consistent with forward scattering emission expected for ϵ Eridani’s disk inclination. Finally, we evaluate the performance of the 3-roll observation strategy, which was first employed in these observations: the gains in contrast are modest, with 20%-30% improvements with respect to the conventional two-roll strategy.
• Wolff, S. G., Gáspár, A., Rieke, G., Leisenring, J. M., Sefilian, A. A., Ygouf, M., & Llop-Sayson, J. (2025). JWST/MIRI Imaging of the Warm Dust Component of the ϵ Eridani Debris Disk. Astronomical Journal, 170(Issue 4). doi:10.3847/1538-3881/adfcd6
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  We present JWST/MIRI observations of the debris disk surrounding the nearby solar analog ϵ Eridani obtained as part of the Archetypal Debris Disk Good Time Observation program. Multiwavelength images from 15, 18, 21, and 25.5 μm show a smooth dust distribution with no evidence of sculpting by massive planets outside of 5 au. Maps of the color temperature and opacity constrain the dust properties, while radiative transfer modeling of a warm dust component traces the interaction between the debris disk and ϵ Eridani b (∼3.5 au). Dynamical and collisional modeling further shows that the disk morphology is dominated by dust produced in the outer planetesimal belt (∼70 au) moving inward via stellar wind drag. We confirm the presence of a disk interior to the ϵ Eri b orbit first detected from mid-IR interferometry. Drag-dominated inner disk regions have also been observed around Vega and Fomalhaut, hinting at the diversity of asteroid belt analogs.
• Xie, C., Chen, C. H., Lisse, C. M., Hines, D. C., Beck, T., Betti, S. K., Pinilla-Alonso, N., Ingebretsen, C., Worthen, K., Gáspár, A., Wolff, S. G., Bolin, B. T., Pueyo, L., Perrin, M. D., Stansberry, J. A., & Leisenring, J. M. (2025). Water ice in the debris disk around HD 181327. Nature, 641(Issue 8063). doi:10.1038/s41586-025-08920-4
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  Debris disks are exoplanetary systems that contain planets, minor bodies (asteroids, Kuiper belt objects, comets and so on) and micrometre-sized debris dust1. Because water ice is the most common frozen volatile, it plays an essential role in the formation of planets2,3 and minor bodies. Although water ice has been commonly found in Kuiper belt objects and comets in the Solar System4, no definitive evidence for water ice in debris disks has been obtained to date1. Here we report the discovery of water ice in the HD 181327 debris disk using the near-infrared spectrograph onboard the James Webb Space Telescope. We detected the solid-state broad absorption feature of water ice at 3 µm including a distinct Fresnel peak at 3.1 µm, which is indicative of large, crystalline water-ice particles. Gradients in the water-ice feature as a function of stellocentric distance reveal a dynamic environment in which water ice is destroyed and replenished. We estimated the water-ice mass fractions as ranging from 0.1% at approximately 85 au to 21% at approximately 113 au, indicating the presence of a water-ice reservoir in the HD 181327 disk beyond the snow line. The icy bodies that release water ice in HD 181327 are probably the extra-solar counterparts of water-ice-rich Kuiper belt objects in our Solar System.
• Bajaj, N. S., Pascucci, I., Gorti, U., Alexander, R., Sellek, A., Morrison, J., Gaspar, A., Clarke, C., Xie, C., Ballabio, G., & Deng, D. (2024). JWST MIRI MRS Observations of T Cha: Discovery of a Spatially Resolved Disk Wind. Astronomical Journal, 167(Issue 3). doi:10.3847/1538-3881/ad22e1
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  Understanding when and how circumstellar disks disperse is crucial to constrain planet formation and migration. Thermal winds powered by high-energy stellar photons have long been theorized to drive disk dispersal. However, evidence for these winds is currently based only on small (∼3-6 km s−1) blueshifts in [Ne ii] 12.81 μm lines, which does not exclude MHD winds. We report JWST MIRI MRS spectro-imaging of T Cha, a disk with a large dust gap (∼30 au in radius) and blueshifted [Ne ii] emission. We detect four forbidden noble gas lines, [Ar ii], [Ar iii], [Ne ii], and [Ne iii], of which [Ar iii] is the first detection in any protoplanetary disk. We use line flux ratios to constrain the energy of the ionizing photons and find that argon is ionized by extreme ultraviolet, whereas neon is most likely ionized by X-rays. After performing continuum and point-spread function subtraction on the integral field unit cube, we discover a spatial extension in the [Ne ii] emission off the disk continuum emission. This is the first spatially resolved [Ne ii] disk wind emission. The mostly ionic spectrum of T Cha, in combination with the extended [Ne ii] emission, points to an evolved stage for any inner MHD wind and is consistent with the existence of an outer thermal wind ionized and driven by high-energy stellar photons. This work acts as a pathfinder for future observations aiming at investigating disk dispersal using JWST.
• Dicken, D., Shivaei, I., Guillard, P., Libralato, M., Glasse, A., Gordon, K., Cossou, C., Kavanagh, P., Temim, T., Flagey, N., Klaassen, P., Rieke, G., Wright, G., Alberts, S., Azzollini, R., Bouchet, P., Bright, S., Cracraft, M., Coulais, A., , Detre, O., et al. (2024). JWST MIRI flight performance: Imaging. Astronomy and Astrophysics, 689(Issue). doi:10.1051/0004-6361/202449451
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  The Mid-Infrared Instrument (MIRI) aboard the James Webb Space Telescope (JWST) provides the observatory with a huge advance in mid-infrared imaging and spectroscopy covering the wavelength range of 5a 28 μm. This paper describes the performance and characteristics of the MIRI imager as understood during observatory commissioning activities, and through its first year of science operations. We discuss the measurements and results of the imagera-s point spread function, flux calibration, background, distortion and flat fields as well as results pertaining to best observing practices for MIRI imaging, and discuss known imaging artefacts that may be seen during or after data processing. Overall, we show that the MIRI imager has met or exceeded all its pre-flight requirements, and we expect it to make a significant contribution to mid-infrared science for the astronomy community for years to come.
• Lawson, K., Schlieder, J., Leisenring, J., Bogat, E., Beichman, C., Bryden, G., Groff, T., McElwain, M., Meyer, M., Barclay, T., Calissendorff, P., De Furio, M., Li, Y., Rieke, M., Ygouf, M., Greene, T., Girard, J., Gennaro, M., Kammerer, J., , Rest, A., et al. (2024). JWST/NIRCam Detection of the Fomalhaut C Debris Disk in Scattered Light. Astrophysical Journal Letters, 967(1). doi:10.3847/2041-8213/ad4496
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  Observations of debris disks offer important insights into the formation and evolution of planetary systems. Though M dwarfs make up approximately 80% of nearby stars, very few M dwarf debris disks have been studied in detail—making it unclear how or if the information gleaned from studying debris disks around more massive stars extends to the more abundant M dwarf systems. We report the first scattered-light detection of the debris disk around the M4 star Fomalhaut C using JWST's Near Infrared Camera (NIRCam; 3.6 and 4.4 μm). This result adds to the prior sample of only four M dwarf debris disks with detections in scattered light and marks the latest spectral type and oldest star among them. The size and orientation of the disk in these data are generally consistent with the prior Atacama Large Millimeter/submillimeter Array submillimeter detection. Though no companions are identified, these data provide strong constraints on their presence—with sensitivity sufficient to recover sub-Saturn mass objects in the vicinity of the disk. This result illustrates the unique capability of JWST to uncover elusive M dwarf debris disks in scattered light and lays the groundwork for deeper studies of such objects in the 2-5 μm regime.
• Sellek, A. D., Bajaj, N. S., Pascucci, I., Clarke, C. J., Alexander, R., Xie, C., Ballabio, G., Deng, D., Gorti, U., Gaspar, A., & Morrison, J. (2024). Modeling JWST MIRI-MRS Observations of T Cha: Mid-IR Noble Gas Emission Tracing a Dense Disk Wind. Astronomical Journal, 167(Issue 5). doi:10.3847/1538-3881/ad34ae
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  [Ne ii] 12.81 μm emission is a well-used tracer of protoplanetary disk winds due to its blueshifted line profile. Mid-Infrared Instrument (MIRI)-Medium Resolution Spectrometer (MRS) recently observed T Cha, detecting this line along with lines of [Ne iii], [Ar ii], and [Ar iii], with the [Ne ii] and [Ne iii] lines found to be extended while the [Ar ii] was not. In this complementary work, we use these lines to address long-debated questions about protoplanetary disk winds regarding their mass-loss rate, the origin of their ionization, and the role of magnetically driven winds as opposed to photoevaporation. To this end, we perform photoionization radiative transfer on simple hydrodynamic wind models to map the line emission. We compare the integrated model luminosities to those observed with MIRI-MRS to identify which models most closely reproduce the data and produce synthetic images from these to understand what information is captured by measurements of the line extents. Along with the low degree of ionization implied by the line ratios, the relative compactness of [Ar ii] compared to [Ne ii] is particularly constraining. This requires Ne ii production by hard X-rays and Ar ii production by soft X-rays (and/or EUV) in an extended (≳10 au) wind that is shielded from soft X-rays, necessitating a dense wind with material launched on scales down to ∼1 au. Such conditions could be produced by photoevaporation, whereas an extended magnetohydrodynamic (MHD) wind producing equal shielding would likely underpredict the line fluxes. However, a tenuous inner MHD wind may still contribute to shielding the extended wind. This picture is consistent with constraints from spectrally resolved line profiles.
• Su, K. Y., Gáspár, A., Rieke, G. H., Malhotra, R., Matrá, L., Wolff, S. G., Leisenring, J. M., Beichman, C., & Ygouf, M. (2024). Imaging of the Vega Debris System Using JWST/MIRI. Astrophysical Journal, 977(Issue 2). doi:10.3847/1538-4357/ad8cde
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  We present images of the Vega planetary debris disk obtained at 15.5, 23, and 25.5 μm with the Mid-Infrared Instrument on JWST. The debris system is remarkably symmetric, smooth, and centered accurately on the star. There is a broad Kuiper-belt-analog ring at ∼80-170 au that coincides with the planetesimal belt detected with the Atacama Large Millimeter/submillimeter Array at 1.34 mm. The interior of the broad belt is filled with warm debris that shines most efficiently at mid-infrared, along with a shallow flux dip/gap at 60 au from the star. These qualitative characteristics argue against any Saturn-mass planets orbiting the star outside of about 10 au, assuming the unseen planet would be embedded in the very broad planetesimal disk from a few to hundreds of astronomical units. We find that the distribution of dust detected interior to the broad outer belt is consistent with grains being dragged inward by the Poynting-Robertson effect. Under the drag-dominated disk assumption, tighter constraints can be derived for planets in specific locations; for example, any planet shepherding the inner edge of the outer belt is likely to be less than six Earth masses. The disk surface brightness profile along with the available infrared photometry suggest a disk inner edge near ∼3−5 au, disconnected from the sub-astronomical-unit region that gives rise to the hot near-infrared excess. The gap between the hot, sub-astronomical-unit zone and the inner edge of the warm debris might be shepherded by a modest-mass, Neptune-size planet.
• Wolff, S., Rieke, G., Leisenring, J., Su, K., Wilner, D., Ygouf, M., Ballering, N., Gáspár, A., & Matrà, L. (2024). Deep Search for a Scattered Light Dust Halo Around Vega with the Hubble Space Telescope. Astronomical Journal, 168(6). doi:10.3847/1538-3881/ad67cb
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  We present a provisory scattered-light detection of the Vega debris disk using deep Hubble Space Telescope (HST) coronagraphy (PID 16666). At only 7.7 pc, Vega is immensely important in debris disk studies both for its prominence and also because it allows the highest physical resolution among all debris systems relative to temperature zones around the star. We employ the STIS coronagraph's widest wedge position and classical reference differential imaging to achieve among the lowest surface-brightness sensitivities to date (∼4 mJy arcsec-2 ) at wide separations using 32 orbits in Cycle 29. We detect a halo extending from the inner edge of our effective inner working angle at 10 5 out to the photon noise floor at 30' (80-230 au). The face-on orientation of the system and the lack of a perfectly color-matched point-spread function star have posed significant challenges to the reductions, particularly regarding artifacts from the imperfect color matching. However, we find that a halo of small dust grains provides the best explanation for the observed signal. Unlike Fomalhaut (a close twin to Vega in luminosity, distance, and age), there is no clear distinction in scattered light between the parent planetesimal belt observed with the Atacama Large Millimeter/submillimeter Array and the extended dust halo. These HST observations complement JWST GTO Cycle 1 observations of the system with NIRCam and MIRI.
• Ygouf, M., Beichman, C., Llop-Sayson, J., Bryden, G., Leisenring, J., Krist, J., Rieke, M., Rieke, G., Wolff, S., Roellig, T., Su, K., Hainline, K., Hodapp, K., Greene, T., Meyer, M., Kelly, D., Misselt, K., Stansberry, J., Boyer, M., , Johnstone, D., et al. (2024). Searching for Planets Orbiting Fomalhaut with JWST/NIRCam. Astronomical Journal, 167(1). doi:10.3847/1538-3881/ad08c8
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  We report observations with the JWST/NIRCam coronagraph of the Fomalhaut (α PsA) system. This nearby A star hosts a complex debris disk system discovered by the IRAS satellite. Observations in F444W and F356W filters using the round 430R mask achieve a contrast ratio of ∼4 × 10−7 at 1″ and ∼4 × 10−8 outside of 3″. These observations reach a sensitivity limit of 0.7 mag (Vega) color. Whether this object is a background galaxy, brown dwarf, or a Jovian-mass planet in the Fomalhaut system will be determined by an approved Cycle 2 follow-up program. Finally, we set upper limits to any scattered light from the outer ring, placing a weak limit on the dust albedo at F356W and F444W.
• , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2023). The James Webb Space Telescope Mission. Publications of the Astronomical Society of the Pacific, 135(1048). doi:10.1088/1538-3873/acd1b5
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  Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.
• Lawson, K., Schlieder, J., Leisenring, J., Bogat, E., Beichman, C., Bryden, G., Groff, T., McElwain, M., Meyer, M., Barclay, T., Calissendorff, P., De Furio, M., Ygouf, M., Boccaletti, A., Greene, T., Krist, J., Plavchan, P., Rieke, M., Roellig, T., , Stansberry, J., et al. (2023). JWST/NIRCam Coronagraphy of the Young Planet-hosting Debris Disk AU Microscopii. Astronomical Journal, 166(4). doi:10.3847/1538-3881/aced08
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  High-contrast imaging of debris disk systems permits us to assess the composition and size distribution of circumstellar dust, to probe recent dynamical histories, and to directly detect and characterize embedded exoplanets. Observations of these systems in the infrared beyond 2-3 μm promise access to both extremely favorable planet contrasts and numerous scattered-light spectral features—but have typically been inhibited by the brightness of the sky at these wavelengths. We present coronagraphy of the AU Microscopii (AU Mic) system using JWST’s Near Infrared Camera (NIRCam) in two filters spanning 3-5 μm. These data provide the first images of the system’s famous debris disk at these wavelengths and permit additional constraints on its properties and morphology. Conducting a deep search for companions in these data, we do not identify any compelling candidates. However, with sensitivity sufficient to recover planets as small as ∼0.1 Jupiter masses beyond ∼2″ (∼20 au) with 5σ confidence, these data place significant constraints on any massive companions that might still remain at large separations and provide additional context for the compact, multiplanet system orbiting very close-in. The observations presented here highlight NIRCam’s unique capabilities for probing similar disks in this largely unexplored wavelength range, and they provide the deepest direct imaging constraints on wide-orbit giant planets in this very well-studied benchmark system.
• Morrison, J. E., Dicken, D., Argyriou, I., Ressler, M. E., Gordon, K. D., Regan, M. W., Cracraft, M., Rieke, G. H., Engesser, M., Alberts, S., Alvarez-Marquez, J., Colbert, J. W., Fox, O. D., Gasman, D., Law, D. R., Garcia Marin, M., Gáspár, A., Guillard, P., Kendrew, S., , Labiano, A., et al. (2023). JWST MIRI Flight Performance: Detector Effects and Data Reduction Algorithms. Publications of the Astronomical Society of the Pacific, 135(Issue 1049). doi:10.1088/1538-3873/acdea6
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  The detectors in the Mid-Infrared Instrument (MIRI) of the James Webb Space Telescope (JWST) are arsenic-doped silicon impurity band conduction (Si:As IBC) devices and are direct descendants of the Spitzer IRAC long wavelength arrays (channels 3 and 4). With appropriate data processing, they can provide excellent performance. In this paper we discuss the various non-ideal behaviors of these detectors that need to be addressed to realize their potential. We have developed a set of algorithms toward this goal, building on experience with previous similar detector arrays. The MIRI-specific stage 1 pipeline algorithms, of a three stage JWST calibration pipeline, were developed using pre-flight tests on the flight detectors and flight spares and have been refined using flight data. This paper describes these algorithms, which are included in the first stage of the JWST Calibration Pipeline for the MIRI instrument.
• Wolff, S., H. Rieke, G., Ballering, N., Ygouf, M., & Gáspár, A. (2023). Hiding Dust around ϵ Eridani. Astronomical Journal, 165(3). doi:10.3847/1538-3881/acac83
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  With a Jupiter-like exoplanet and a debris disk with both asteroid and Kuiper Belt analogs, ϵ Eridani has a fascinating resemblance to our expectations for a young solar system. We present a deep Hubble Space Telescope/Space Telescope Imaging Spectrograph coronographic data set using eight orbit visits and the point-spread function calibrator δ Eridani. While we were unable to detect the debris disk, we place stringent constraints on the scattered light surface brightness of ∼ 4 μ Jy arcsec − 2 . We combine this scattered light detection limit with a reanalysis of archival near- and mid-infrared observations and a dynamical model of the full planetary system to refine our model of the ϵ Eridani debris disk components. Radiative transfer modeling suggests an asteroid belt analog inside of 3 au, an intermediate disk component in the 6-37 au region, and a Kuiper Belt analog colocated with the narrow belt observed in the millimeter (69 au). Modeling also suggests a large minimum grain size requiring either very porous grains or a suppression of small grain production, and a radially stratified particle size distribution. The inner disk regions require a steep power-law slope (s −3.8 where s is the grain size) weighted toward smaller grains and the outer disk prefers a shallower slope (s −3.4) with a minimum particle size of >2 μm. These conclusions will be enhanced by upcoming coronagraphic observations of the system with the James Webb Space Telescope, which will pinpoint the radial location of the dust belts and further diagnose the dust particle properties.
• Wolff, S., Rieke, G., Leisenring, J., Morrison, J., Su, K., Ward-Duong, K., Aguilar, J., Ygouf, M., Beichman, C., Llop-Sayson, J., Bryden, G., & Gáspár, A. (2023). Spatially resolved imaging of the inner Fomalhaut disk using JWST/MIRI. Nature Astronomy, 7(7). doi:10.1038/s41550-023-01962-6
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  Planetary debris disks around other stars are analogous to the asteroid and Kuiper belts in the Solar System. Their structure reveals the configuration of small bodies and provides hints for the presence of planets. The nearby star Fomalhaut hosts one of the most prominent debris disks, resolved by the Hubble Space Telescope, Spitzer, Herschel and the Atacama Large Millimeter Array. Images of this system at mid-infrared wavelengths using JWST/MIRI not only show the narrow Kuiper belt-analogue outer ring, but also that (1) what was thought from indirect evidence to be an asteroid-analogue structure is instead broad, extending outward into the outer system, and (2) there is an intermediate belt, probably shepherded by an unseen planet. The newly discovered belt is demarcated by an inner gap, located at ~78 au, and it is misaligned relative to the outer belt. The previously known collisionally generated dust cloud, Fomalhaut b, could have originated from this belt, suggesting increased dynamical stirring and collision rates there. We also discovered a large dust cloud within the outer ring, possible evidence of another dust-creating collision. Taken together with previous observations, Fomalhaut appears to be the site of a complex and possibly dynamically active planetary system.
• Wright, G. S., Rieke, G. H., Glasse, A., Ressler, M., García Marín, M., Aguilar, J., Alberts, S., Álvarez-Márquez, J., Argyriou, I., Banks, K., Baudoz, P., Boccaletti, A., Bouchet, P., Bouwman, J., Brandl, B. R., Breda, D., Bright, S., Cale, S., Colina, L., , Cossou, C., et al. (2023). The Mid-infrared Instrument for JWST and Its In-flight Performance. Publications of the Astronomical Society of the Pacific, 135(Issue 1046). doi:10.1088/1538-3873/acbe66
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  The Mid-Infrared Instrument (MIRI) extends the reach of the James Webb Space Telescope (JWST) to 28.5 μm. It provides subarcsecond-resolution imaging, high sensitivity coronagraphy, and spectroscopy at resolutions of λ/Δλ ∼ 100-3500, with the high-resolution mode employing an integral field unit to provide spatial data cubes. The resulting broad suite of capabilities will enable huge advances in studies over this wavelength range. This overview describes the history of acquiring this capability for JWST. It discusses the basic attributes of the instrument optics, the detector arrays, and the cryocooler that keeps everything at approximately 7 K. It gives a short description of the data pipeline and of the instrument performance demonstrated during JWST commissioning. The bottom line is that the telescope and MIRI are both operating to the standards set by pre-launch predictions, and all of the MIRI capabilities are operating at, or even a bit better than, the level that had been expected. The paper is also designed to act as a roadmap to more detailed papers on different aspects of MIRI.
• Boccaletti, A., Cossou, C., Baudoz, P., Lagage, P., Dicken, D., Glasse, A., Hines, D., Aguilar, J., Detre, O., Nickson, B., Noriega-Crespo, A., Labiano, A., Stark, C., Rouan, D., Reess, J., Wright, G., Rieke, G., Garcia Marin, M., Lajoie, C., , Girard, J., et al. (2022). JWST/MIRI coronagraphic performances as measured on-sky. Astronomy and Astrophysics, 667(Issue). doi:10.1051/0004-6361/202244578
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  Context. Characterization of directly imaged exoplanets is one of the most eagerly anticipated science functions of the James Webb Space Telescope. MIRI, the mid-IR instrument, has the capability to provide unique spatially resolved photometric data points in a spectral range never before achieved for such objects. Aims. We aim to present the very first on-sky contrast measurements of the MIRI coronagraphs. In addition to a classical Lyot coronagraph at the longest wavelength, this observing mode implements the concept of the four-quadrant phase mask for the very first time in a space telescope. Methods. We observed single stars together with a series of reference stars to measure raw contrasts as they are delivered on the detector, as well as reference-subtracted contrasts. Results. The MIRI coronagraphs achieve raw contrasts better than 10-3 at the smallest angular separations (within 1) and about 10-5 farther out (beyond 5 6). Subtracting the residual diffracted light left behind the coronagraph has the potential to bring the final contrast down to the background-and detector-limited noise floor at most angular separations (a few times 10-5 at less than 1). Conclusions. The MIRI coronagraphs behave as expected from simulations. In particular, the raw contrasts for all four coronagraphs are fully consistent with the diffractive model. Contrasts obtained by subtracting reference stars also meet expectations and are fully demonstrated for two four-quadrant phase masks (F1065C and F1140C). The worst contrast, measured at F1550C, is very likely due to a variation in the phase aberrations at the primary mirror during the observations, and not an issue with the coronagraph itself. We did not perform reference star subtraction with the Lyot mask at F2300C, but we anticipate that it would bring the contrast down to the noise floor.
• Defr{`ere}, D., Hinz, P., Kennedy, G., Stone, J., Rigley, J., Ertel, S., Gaspar, A., Bailey, V., Hoffmann, W., Mennesson, B., Millan-Gabet, R. .., Danchi, W., Absil, O., Arbo, P., Beichman, C., Bonavita, M., Brusa, G., Bryden, G., Downey, E., , Esposito, S., et al. (2021). "The HOSTS Survey: Evidence for an Extended Dust Disk and Constraints on the Presence of Giant Planets in the Habitable Zone of {ensuremath{beta} Leo}". aj, 161(4), 186.
• G{'asp'ar}, A., Rieke, G. H., Guillard, P., Dicken, D., Gastaud, R., Alberts, S., Morrison, J., Ressler, M. E., Argyriou, I., & Glasse, A. (2021). "The Quantum Efficiency and Diffractive Image Artifacts of Si:As IBC mid-IR Detector Arrays at 5-10 {ensuremath{mu}m: Implications for the JWST/MIRI Detectors}". pasp, 133(1019), 014504.
• Gáspár, A., Rieke, G. H., Guillard, P., Dicken, D., Gastaud, R., Alberts, S., Morrison, J., Ressler, M. E., Argyriou, I., & Glasse, A. (2021). The quantum efficiency and diffractive image artifacts of Si:As ibc mid-ir detector arrays at 5–10 μm: Implications for the jwst/miri detectors. Publications of the Astronomical Society of the Pacific, 133(Issue 1019). doi:10.1088/1538-3873/abcd04
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  Arsenic doped back illuminated blocked impurity band (BIBIB) silicon detectors have advanced near and mid-IR astronomy for over thirty years; they have high quantum efficiency (QE), especially at wavelengths longer than 10 μm, and a large spectral range. Their radiation hardness is also an asset for space based instruments. Three examples of Si:As BIBIB arrays are used in the Mid-InfraRed Instrument (MIRI) of the James Webb Space Telescope (JWST), observing between 5 and 28 μm. In this paper, we analyze the parameters leading to high quantum efficiency (up to ∼60%) for the MIRI devices between 5 and 10 μm. We also model the cross-shaped artifact that was first noticed in the 5.7 and 7.8 μm Spitzer/IRAC images and has since also been imaged at shorter wavelength (≤10 μm) laboratory tests of the MIRI detectors. The artifact is a result of internal reflective diffraction off the pixel-defining metallic contacts to the readout detector circuit. The low absorption in the arrays at the shorter wavelengths enables photons diffracted to wide angles to cross the detectors and substrates multiple times. This is related to similar behavior in other back illuminated solid-state detectors with poor absorption, such as conventional CCDs operating near 1 μm. We investigate the properties of the artifact and its dependence on the detector architecture with a quantum-electrodynamic (QED) model of the probabilities of various photon paths. Knowledge of the artifact properties will be especially important for observations with the MIRI LRS and MRS spectroscopic modes.
• Rieke, G., Su, K., Melis, C., & G{'asp'ar}, A. (2021). "Extreme Variability of the V488 Persei Debris Disk". apj, 918(2), 71.
• Ertel, S., Defr{`ere}, D., Hinz, P., Mennesson, B., Kennedy, G., Danchi, W., Gelino, C., Hill, J., Hoffmann, W., Mazoyer, J., Rieke, G., Shannon, A., Stapelfeldt, K., Spalding, E., Stone, J., Vaz, A., Weinberger, A., Willems, P., Absil, O., , Arbo, P., et al. (2020). "The HOSTS Survey for Exozodiacal Dust: Observational Results from the Complete Survey". aj, 159(4), 177.
• Gaspar, A., & Rieke, G. (2020). "New HST data and modeling reveal a massive planetesimal collision around Fomalhaut". Proceedings of the National Academy of Science, 117(18), 9712-9722.
• Grady, C., Wisniewski, J., Schneider, G., Boccaletti, A., Gaspar, A., Debes, J., Hines, D., Stark, C., Thalmann, C., Lagrange, A. -., Augereau, J. -., Sezestre, E., Milli, J., Henning, T., & Kuchner, M. (2020). "The Eroding Disk of AU Mic". apjl, 889(1), L21.
• Kuchner, M., Henning, T., Milli, J., Sezestre, E., Augereau, J., Thalmann, C., Legrange, A., Stark, C. C., Hines, D. C., Debes, J. H., Gaspar, A., Boccaletti, A., Schneider, G., Wisniewski, J., & Grady, C. A. (2020). The Eroding Disk of AU Mic. Astrophysical Journal, 889, L21. doi:https://doi.org/10.3847/2041-8213/ab65bb
• Su, K. Y., Rieke, G. H., Melis, C., Jackson, A. P., Smith, P. S., Meng, H. Y., & G{'asp'ar}, A. (2020). "Mid-infrared Studies of HD 113766 and HD 172555: Assessing Variability in the Terrestrial Zone of Young Exoplanetary Systems". apj, 898(1), 21.
• Bailey, V. P., Bryden, G., Danchi, W. C., Debes, J. H., Defrere, D., Ertel, S., Gaspar, A., Haniff, C. A., Hasegawa, Y., Hinz, P. M., Kasdin, J., Kennedy, G. M., Lisse, C., Lyra, W., Macintosh, B., Mawet, D., Mennesson, B., Millan-gabet, R., Roberge, A., , Scott, N. J., et al. (2019). Interplanetary dust around main sequence stars: origin, magnitude, and implications for exoplanet habitability searches. Bulletin of the American Astronomical Society, 51(3).
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  The brightness and spatial distribution of warm (~200K) dust structures located within a few AU We motivate and identify here the main instrumental / observational advances required to gain further insights into the origins of exozodiacal dust clouds and better understand their impact on planetary habitability and habitability searches.
• Ballering, N. P., Chen, C., Duchene, G., Gaspar, A., Kolokolova, L., Lisse, C. M., Mazoyer, J., Moro-martin, A., Ren, B., Su, K. Y., & Wyatt, M. C. (2019). Debris Disk Composition: A Diagnostic Tool for Planet Formation and Migration. Bulletin of the American Astronomical Society, 51(3).
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  Detailed studies of debris disk composition studies can address the scientific questions: (1) Are debris disk minor bodies similar to asteroids and comets in our Solar System? (2) Do planets separate circumstellar material into distinct reservoirs and/or mix material during planet migration?
• Baruteau, C., Krijt, S., Williams, J., Andrews, S. M., Baruteau, C., Belle, G. V., Berger, J., Bergin, E. A., Birnstiel, T., Bowler, B. P., Brogan, C. L., Brummelaar, T. T., Chandler, C. J., Currie, T., Cuzzi, J. N., D'angelo, G., Dong, R., Duchene, G., Dutrey, A., , Ercolano, B., et al. (2019). Observing Planetary Systems in the Making. Bulletin of the American Astronomical Society, 51(3).
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  We discuss science cases to support the development of sub-au imaging capabilities to image forming planets in the terrestrial region of nearby proto-planetary disks.
• Bitsch, B., Casassus, S., Cuello, N., Currie, T., Gaspar, A., Haworth, T., Isella, A., Jang-condell, H., Klahr, H., Leigh, N., Lodato, G., Low, M. M., Lyra, W., Maddison, S., Mamatsashvili, G. R., Mcnally, C., Perez, S., Ricci, L., Sengupta, D., , Stamatellos, D., et al. (2019). Planet formation — The case for large efforts on the computational side. Bulletin of the American Astronomical Society, 51(3).
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  As advances are expected with ground based interferometers and the James Webb Space Telescope in the next decade, the central point of this white paper is what efforts on the computational side are required in the next decade to advance our theoretical understanding, explain the observational data, and guide new observations?
• Gaspar, A., Apai, D., Augereau, J., Ballering, N. P., Beichman, C. A., Boccaletti, A., Booth, M., Bowler, B. P., Bryden, G., Chen, C. H., Currie, T., Danchi, W. C., Debes, J., Defr{`ere}, D., Ertel, S., Jackson, A. P., Kalas, P. G., Kennedy, G. M., Kenworthy, M. A., , Kim, J. S., et al. (2019). Modeling Debris Disk Evolution. baas, 51(3), 69.
• Su, K. Y., Jackson, A. P., G{'asp'ar}, A., Rieke, G. H., Dong, R., Olofsson, J., Kennedy, G., Leinhardt, Z. M., Malhotra, R., Hammer, M., Meng, H. Y., Rujopakarn, W., Rodriguez, J. E., Pepper, J., Reichart, D., James, D., & Stassun, K. G. (2019). Extreme Debris Disk Variability: Exploring the Diverse Outcomes of Large Asteroid Impacts During the Era of Terrestrial Planet Formation. aj, 157(5), 202.
• Thalmann, C., Stark, C. C., Sezestre, E., Milli, J., Lagrange, A., Kuchner, M. J., Hines, D. C., Henning, T. K., Gaspar, A., Debes, J. H., Brown, A., Boccaletti, A., Augereau, J., Lawaon, K. D., Hebb, L., Grady, C. A., Schneider, G., Davenport, J. R., Kowalski, A. F., & Wisniewski, J. P. (2019). High-fidelity Imaging of the Inner AU Mic Debris Disk: Evidence of Differential Wind Sculpting?. Astrophysical Journal, 883, L8. doi:Astrophysical Journal
• Absil, O., Arbo, P., Bailey, V. P., Beichman, C., Bryden, G., Danchi, W. C., Defrere, D., Downey, E. C., Durney, O., Ertel, S., Esposito, S., Gaspar, A., Gelino, C. R., Grenz, P., Haniff, C. A., Hill, J. M., Hinz, P. M., Hoffmann, W. F., Kennedy, G. M., , Leisenring, J. M., et al. (2018). The HOSTS survey - Exozodiacal dust measurements for 30 stars. The Astronomical Journal, 155(5), 194. doi:10.3847/1538-3881/aab717
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  The Hunt for Observable Signatures of Terrestrial Systems survey searches for dust near the habitable zones (HZs) around nearby, bright main-sequence stars. We use nulling interferometry in the N band to suppress the bright stellar light and to probe for low levels of HZ dust around the 30 stars observed so far. Our overall detection rate is 18%, including four new detections, among which are the first three around Sun-like stars and the first two around stars without any previously known circumstellar dust. The inferred occurrence rates are comparable for early-type and Sun-like stars, but decrease from 60^(+16)_(-21)% for stars with previously detected cold dust to 8^(+10)_(-3)% for stars without such excess, confirming earlier results at higher sensitivity. For completed observations on individual stars, our sensitivity is five to ten times better than previous results. Assuming a lognormal excess luminosity function, we put upper limits on the median HZ dust level of 13 zodis (95% confidence) for a sample of stars without cold dust and of 26 zodis when focusing on Sun-like stars without cold dust. However, our data suggest that a more complex luminosity function may be more appropriate. For stars without detectable Large Binocular Telescope Interferometer (LBTI) excess, our upper limits are almost reduced by a factor of two, demonstrating the strength of LBTI target vetting for future exo-Earth imaging missions. Our statistics are limited so far, and extending the survey is critical to informing the design of future exo-Earth imaging surveys.
• Ertel, S., Defr{\`ere}, D., Hinz, P., Mennesson, B., Kennedy, G., Danchi, W., Gelino, C., Hill, J., Hoffmann, W., Rieke, G., Shannon, A., Spalding, E., Stone, J., Vaz, A., Weinberger, A., Willems, P., Absil, O., Arbo, P., Bailey, V., , Beichman, C., et al. (2018). The HOSTS Survey\mdashExozodiacal Dust Measurements for 30 Stars. \aj, 155, 194.
• Jackson, A., Su, K., Dong, R., Rieke, G., & Gaspar, A. (2018). Observing Giant, Planet Forming Impacts in Exoplanetary Systems. LPI Contributions, 2107, 2019.
• Schneider, G., Debes, J., Grady, C., G{\'asp\'ar}, A., Henning, T., Hines, D., Kuchner, M., Perrin, M., & Wisniewski, J. (2018). The HR 4796A Debris System: Discovery of Extensive Exo-ring Dust Material. \aj, 155, 77.
• Su, K., Jackson, A., Dong, R., Rieke, G., & Gaspar, A. (2018). Short-Term Disk Flux Modulations due to the Orbital Evolution of Impact Produced Clouds of Dust in NGC2547-ID8. LPI Contributions, 2107, 2025.
• Ballering, N., Rieke, G., Su, K., & G{\'asp\'ar}, A. (2017). What Sets the Radial Locations of Warm Debris Disks?. \apj, 845, 120.
• Debes, J., Poteet, C., Jang-Condell, H. .., Gaspar, A., Hines, D., Kastner, J., Pueyo, L., Rapson, V., Roberge, A., Schneider, G., & Weinberger, A. (2017). Chasing Shadows: Rotation of the Azimuthal Asymmetry in the TW Hya Disk. \apj, 835, 205.
• Meng, H., Rieke, G., Su, K., & G{\'asp\'ar}, A. (2017). The First 40 Million Years of Circumstellar Disk Evolution: The Signature of Terrestrial Planet Formation. \apj, 836, 34.
• Ballering, N., Su, K., Rieke, G., & G{\'asp\'ar}, A. (2016). A Comprehensive Dust Model Applied to the Resolved Beta Pictoris Debris Disk from Optical to Radio Wavelengths. \apj, 823, 108.
• Ballering, N., Su, K., Rieke, G., & Gáspár, A. (2016). A COMPREHENSIVE DUST MODEL APPLIED to the RESOLVED BETA PICTORIS DEBRIS DISK from OPTICAL to RADIO WAVELENGTHS. Astrophysical Journal, 823(2). doi:10.3847/0004-637X/823/2/108
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  We investigate whether varying the dust composition (described by the optical constants) can solve a persistent problem in debris disk modeling - the inability to fit the thermal emission without overpredicting the scattered light. We model five images of the β Pictoris disk: two in scattered light from the Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph at 0.58 μm and HST/Wide Field Camera 3 (WFC 3) at 1.16 μm, and three in thermal emission from Spitzer/Multiband Imaging Photometer for Spitzer (MIPS) at 24 μm, Herschel/PACS at 70 μm, and Atacama Large Millimeter/submillimeter Array at 870 μm. The WFC3 and MIPS data are published here for the first time. We focus our modeling on the outer part of this disk, consisting of a parent body ring and a halo of small grains. First, we confirm that a model using astronomical silicates cannot simultaneously fit the thermal and scattered light data. Next, we use a simple generic function for the optical constants to show that varying the dust composition can improve the fit substantially. Finally, we model the dust as a mixture of the most plausible debris constituents: astronomical silicates, water ice, organic refractory material, and vacuum. We achieve a good fit to all data sets with grains composed predominantly of silicates and organics, while ice and vacuum are, at most, present in small amounts. This composition is similar to one derived from previous work on the HR 4796A disk. Our model also fits the thermal spectral energy distribution, scattered light colors, and high-resolution mid-IR data from T-ReCS for this disk. Additionally, we show that sub-blowout grains are a necessary component of the halo.
• Balog, Z., Bell, C. P., Gaspar, A., Gutermuth, R. A., Kiss, L. L., Muzerolle, J., Rieke, G. H., Siegler, N., Su, K. Y., Vinko, J., & Young, E. T. (2016). PROTOPLANETARY and TRANSITIONAL DISKS in the OPEN STELLAR CLUSTER IC 2395. The Astrophysical Journal, 832(1), 87. doi:10.3847/0004-637x/832/1/87
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  NASA [1255094]; Lendulet Young Researchers Program of the Hungarian Academy of Sciences; National Aeronautics and Space Administration; National Science Foundation
• Balog, Z., Siegler, N., Rieke, G., Kiss, L., Muzerolle, J., Gutermuth, R., Bell, C., Vink{\'o}, J., Su, K., Young, E., & G{\'asp\'ar}, A. (2016). Protoplanetary and Transitional Disks in the Open Stellar Cluster IC 2395. \apj, 832, 87.
• Carson, J. C., Debes, J. H., Gaspar, A., Grady, C. A., Henning, T., Hines, D. C., Jang-condell, H., Kuchner, M. J., Perrin, M. D., Rodigas, T. J., Schneider, G., Stark, C. C., Tamura, M., & Wisniewski, J. P. (2016). DEEP HST/STIS VISIBLE-LIGHT IMAGING OF DEBRIS SYSTEMS AROUND SOLAR ANALOG HOSTS. The Astronomical Journal, 152(3), 64. doi:10.3847/0004-6256/152/3/64
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  Association of Universities for Research in Astronomy, Inc., under NASA [NAS 5-26555]; NASA through STScI [13786]; South Carolina Space Grant Consortium; [12228]
• Defrre, D., Hinz, P., Mennesson, B., Hoffmann, W., Millan-Gabet, R., Skemer, A., Bailey, V., Danchi, W., Downey, E., Durney, O., Grenz, P., Hill, J., McMahon, T., Montoya, M., Spalding, E., Vaz, A., Absil, O., Arbo, P., Bailey, H., , Brusa, G., et al. (2016). NULLING DATA REDUCTION and ON-SKY PERFORMANCE of the LARGE BINOCULAR TELESCOPE INTERFEROMETER. Astrophysical Journal, 824(2). doi:10.3847/0004-637X/824/2/66
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  The Large Binocular Telescope Interferometer (LBTI) is a versatile instrument designed for high angular resolution and high-contrast infrared imaging (1.5-13 μm). In this paper, we focus on the mid-infrared (8-13 μm) nulling mode and present its theory of operation, data reduction, and on-sky performance as of the end of the commissioning phase in 2015 March. With an interferometric baseline of 14.4 m, the LBTI nuller is specifically tuned to resolve the habitable zone of nearby main-sequence stars, where warm exozodiacal dust emission peaks. Measuring the exozodi luminosity function of nearby main-sequence stars is a key milestone to prepare for future exo-Earth direct imaging instruments. Thanks to recent progress in wavefront control and phase stabilization, as well as in data reduction techniques, the LBTI demonstrated in 2015 February a calibrated null accuracy of 0.05% over a 3 hr long observing sequence on the bright nearby A3V star β Leo. This is equivalent to an exozodiacal disk density of 15-30 zodi for a Sun-like star located at 10 pc, depending on the adopted disk model. This result sets a new record for high-contrast mid-infrared interferometric imaging and opens a new window on the study of planetary systems.
• Defr{\`ere}, D., Hinz, P., Mennesson, B., Hoffmann, W., Millan-Gabet, R. .., Skemer, A., Bailey, V., Danchi, W., Downey, E., Durney, O., Grenz, P., Hill, J., McMahon, T., Montoya, M., Spalding, E., Vaz, A., Absil, O., Arbo, P., Bailey, H., , Brusa, G., et al. (2016). Nulling Data Reduction and On-sky Performance of the Large Binocular Telescope Interferometer. \apj, 824, 66.
• G{\'asp\'ar}, A., Rieke, G., & Ballering, N. (2016). The Correlation between Metallicity and Debris Disk Mass. \apj, 826, 171.
• Konishi, M., Grady, C., Schneider, G., Shibai, H., McElwain, M., Nesvold, E., Kuchner, M., Carson, J., Debes, J., Gaspar, A., Henning, T., Hines, D., Hinz, P., Jang-Condell, H. .., Moro-Mart{\'{\i}n}, A., Perrin, M., Rodigas, T., Serabyn, E., Silverstone, M., , Stark, C., et al. (2016). Discovery of an Inner Disk Component around HD 141569 A. \apjl, 818, L23.
• Konishi, M., Grady, C., Schneider, G., Shibai, H., McElwain, M., Nesvold, E., Kuchner, M., Carson, J., Debes, J., Gaspar, A., Henning, T., Hines, D., Hinz, P., Jang-Condell, H., Moro-Martin, A., Perrin, M., Rodigas, T., Serabyn, E., Silverstone, M., , Stark, C., et al. (2016). DISCOVERY of AN INNER DISK COMPONENT AROUND HD 141569 A. Astrophysical Journal Letters, 818(2). doi:10.3847/2041-8205/818/2/L23
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  We report the discovery of a scattering component around the HD 141569 A circumstellar debris system, interior to the previously known inner ring. The discovered inner disk component, obtained in broadband optical light with Hubble Space Telescope/Space Telescope Imaging Spectrograph coronagraphy, was imaged with an inner working angle of 0.″25, and can be traced from 0.″4 (∼46 AU) to 1.″0 (∼116 AU) after deprojection using i = 55°. The inner disk component is seen to forward scatter in a manner similar to the previously known rings, has a pericenter offset of ∼6 AU, and break points where the slope of the surface brightness changes. It also has a spiral arm trailing in the same sense as other spiral arms and arcs seen at larger stellocentric distances. The inner disk spatially overlaps with the previously reported warm gas disk seen in thermal emission. We detect no point sources within 2″ (∼232 AU), in particular in the gap between the inner disk component and the inner ring. Our upper limit of 9 ± 3 MJ is augmented by a new dynamical limit on single planetary mass bodies in the gap between the inner disk component and the inner ring of 1 MJ, which is broadly consistent with previous estimates.
• Rieke, G. H., Gáspár, A., & Ballering, N. P. (2016). Magnetic grain trapping and the hot excesses around early-type stars. Astrophysical Journal, 816(Issue 2). doi:10.3847/0004-637x/816/2/50
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  A significant fraction of main sequence stars observed interferometrically in the near-infrared have slightly extended components that have been attributed to very hot dust. To match the spectrum appears to require the presence of large numbers of very small (
• Rieke, G., G{\'asp\'ar}, A., & Ballering, N. (2016). Magnetic Grain Trapping and the Hot Excesses around Early-type Stars. \apj, 816, 50.
• Schneider, G., Grady, C., Stark, C., Gaspar, A., Carson, J., Debes, J., Henning, T., Hines, D., Jang-Condell, H. .., Kuchner, M., Perrin, M., Rodigas, T., Tamura, M., & Wisniewski, J. (2016). Deep HST/STIS Visible-light Imaging of Debris Systems around Solar Analog Hosts. \aj, 152, 64.
• Beichman, C., Morzinski, K. M., Wyatt, M. C., Absil, O., Arbo, P., Bailey, V. P., Beichman, C. A., Brusa, G., Bryden, G., Danchi, W. C., Defrere, D., Downey, E. C., Durney, O., Esposito, S., Gaspar, A., Grenz, P., Haniff, C. A., Hill, J. M., Hinz, P. M., , Hoffmann, W. F., et al. (2015). FIRST-LIGHT LBT NULLING INTERFEROMETRIC OBSERVATIONS: WARM EXOZODIACAL DUST RESOLVED WITHIN A FEW AU OF η Crv. The Astrophysical Journal, 799(1), 42. doi:10.1088/0004-637x/799/1/42
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  We report on the first nulling interferometric observations with the Large Binocular Telescope Interferometer (LBTI), resolving the N' band (9.81–12.41 μm) emission around the nearby main-sequence star η Crv (F2V, 1–2 Gyr). The measured source null depth amounts to 4.40% ± 0.35% over a field-of-view of 140 mas in radius (~2.6 AU for the distance of η Crv) and shows no significant variation over 35° of sky rotation. This relatively low null is unexpected given the total disk to star flux ratio measured by the Spitzer Infrared Spectrograph (IRS; ~23% across the N' band), suggesting that a significant fraction of the dust lies within the central nulled response of the LBTI (79 mas or 1.4 AU). Modeling of the warm disk shows that it cannot resemble a scaled version of the solar zodiacal cloud unless it is almost perpendicular to the outer disk imaged by Herschel. It is more likely that the inner and outer disks are coplanar and the warm dust is located at a distance of 0.5–1.0 AU, significantly closer than previously predicted by models of the IRS spectrum (~3 AU). The predicted disk sizes can be reconciled if the warm disk is not centrosymmetric, or if the dust particles are dominated by very small grains. Both possibilities hint that a recent collision has produced much of the dust. Finally, we discuss the implications for the presence of dust for the distance where the insolation is the same as Earth's (2.3 AU).
• Defr{\`ere}, D., Hinz, P., Skemer, A., Kennedy, G., Bailey, V., Hoffmann, W., Mennesson, B., Millan-Gabet, R. .., Danchi, W., Absil, O., Arbo, P., Beichman, C., Brusa, G., Bryden, G., Downey, E., Durney, O., Esposito, S., Gaspar, A., Grenz, P., , Haniff, C., et al. (2015). First-light LBT Nulling Interferometric Observations: Warm Exozodiacal Dust Resolved within a Few AU of $\eta$ Crv. \apj, 799, 42.
• Ballering, N., Rieke, G., & G{\'asp\'ar}, A. (2014). Probing the Terrestrial Regions of Planetary Systems: Warm Debris Disks with Emission Features. \apj, 793, 57.
• Gaspar, A., Schrader, W., & Xuan, Y. (2014). Studying ultra-complex crude oil mixtures by using high-field asymmetric waveform ion mobility spectrometry (FAIMS) coupled to an electrospray ionisation-LTQ-orbitrap mass spectrometer.. European journal of mass spectrometry (Chichester, England), 20(1), 43-9. doi:10.1255/ejms.1263
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  High-field asymmetric waveform ion mobility spectrometry (FAIMS) was coupled directly to an LTQ Orbitrap mass spectrometer to analyze a nitrogen-rich crude oil. Analyzing crude oil is extremely difficult because of the complexity, as up to 100,000 different components can be present. Therefore, simplification of crude oil increases the information content because discrimination and suppression effects are reduced. Here, the first results are presented that show that FAIMS can be an important tool for the simplification of complex mixtures. Additionally, the results show that FAIMS is an excellent tool that allows not only a simplification of such complex mixtures, but also shows the separation of isomeric compounds that have the same elemental composition but different structure and conformation.
• G{\'asp\'ar}, A., & Rieke, G. (2014). The Herschel Cold Debris Disks: Confusion with the Extragalactic Background at 160 $\mu$m. \apj, 784, 33.
• Sierchio, J., Rieke, G., Su, K., & G{\'asp\'ar}, A. (2014). The Decay of Debris Disks around Solar-type Stars. \apj, 785, 33.
• G{\'asp\'ar}, A., Rieke, G., & Balog, Z. (2013). The Collisional Evolution of Debris Disks. \apj, 768, 25.
• G{\'asp\'ar}, A., Psaltis, D., Rieke, G., , F. (2012). Modeling Collisional Cascades in Debris Disks: Steep Dust-size Distributions. \apj, 754, 74.
• G{\'asp\'ar}, A., Psaltis, D., {\"Ozel}, F., Rieke, G., & Cooney, A. (2012). Modeling Collisional Cascades in Debris Disks: The Numerical Method. \apj, 749, 14.
• Szalai, T., Vink{\'o}, J., Balog, Z., G{\'asp\'ar}, A., Block, M., & Kiss, L. (2011). Dust formation in the ejecta of the type II-P supernova 2004dj. \aap, 527, A61.
• Krist, J., Stapelfeldt, K., Bryden, G., Rieke, G., Su, K., Chen, C., Beichman, C., Hines, D., Rebull, L., Tanner, A., Trilling, D., Clampin, M., & G{\'asp\'ar}, A. (2010). HST and Spitzer Observations of the HD 207129 Debris Ring. \aj, 140, 1051-1061.
• Balog, Z., Kiss, L., Vink{\'o}, J., Rieke, G., Muzerolle, J., G{\'asp\'ar}, A., Young, E., & Gorlova, N. (2009). Spitzer/IRAC-MIPS Survey of NGC 2451A AND B: Debris Disks at 50-80 Million Years. \apj, 698, 1989-2013.
• G{\'asp\'ar}, A., Rieke, G., Su, K., Balog, Z., Trilling, D., Muzzerole, J., Apai, D., & Kelly, B. (2009). The Low Level of Debris Disk Activity at the Time of the Late Heavy Bombardment: A Spitzer Study of Praesepe. \apj, 697, 1578-1596.
• Mart{\'{\i}nez-Galarza}, J., Kamp, I., Su, K., G{\'asp\'ar}, A., Rieke, G., & Mamajek, E. (2009). Infrared Emission by Dust Around $\lambda$ Bootis Stars: Debris Disks or Thermally Emitting Nebulae?. \apj, 694, 165-173.
• Martínez-Galarza, J. R., Kamp, I., Su, K. Y., Gspr, A., Rieke, G., & Mamajek, E. E. (2009). Infrared emission by dust around λ bootis stars: Debris disks or thermally emitting nebulae?. Astrophysical Journal, 694(Issue 1). doi:10.1088/0004-637x/694/1/165
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  We present a model that describes stellar infrared excesses due to heating of the interstellar (IS) dust by a hot star passing through a diffuse IS cloud. This model is applied to six λ Bootis stars with infrared excesses. Plausible values for the IS medium (ISM) density and relative velocity between the cloud and the star yield fits to the excess emission. This result is consistent with the diffusion/accretion hypothesis that λ Bootis stars (A- to F-type stars with large underabundances of Fe-peak elements) owe their characteristics to interactions with the ISM. This proposal invokes radiation pressure from the star to repel the IS dust and excavate a paraboloidal dust cavity in the IS cloud, while the metal-poor gas is accreted onto the stellar photosphere. However, the measurements of the infrared excesses can also be fit by planetary debris disk models. A more detailed consideration of the conditions to produce λ Bootis characteristics indicates that the majority of infrared-excess stars within the Local Bubble probably have debris disks. Nevertheless, more distant stars may often have excesses due to heating of IS material such as in our model. © 2009 The American Astronomical Society.
• Trilling, D., Apai, D., Balog, Z., Gaspar, A., Kelly, B. C., Muzzerole, J., Rieke, G. H., Su, K. Y., & Trilling, D. E. (2009). THE LOW LEVEL OF DEBRIS DISK ACTIVITY AT THE TIME OF THE LATE HEAVY BOMBARDMENT: A SPITZER STUDY OF PRAESEPE. The Astrophysical Journal, 697(2), 1578-1596. doi:10.1088/0004-637x/697/2/1578
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  We present 24 μm photometry of the intermediate-age open cluster Praesepe. We assemble a catalog of 193 probable cluster members that are detected in optical databases, the Two Micron All Sky Survey (2MASS), and at 24 μm, within an area of ~2.47 deg2. Mid-IR excesses indicating debris disks are found for one early-type and for three solar-type stars. Corrections for sampling statistics yield a 24 μm excess fraction (debris disk fraction) of 6.5% ± 4.1% for luminous and 1.9% ± 1.2% for solar-type stars. The incidence of excesses is in agreement with the decay trend of debris disks as a function of age observed for other cluster and field stars. The values also agree with those for older stars, indicating that debris generation in the zones that emit at 24 μm falls to the older 1-10 Gyr field star sample value by roughly 750 Myr. We discuss our results in the context of previous observations of excess fractions for early- and solar-type stars. We show that solar-type stars lose their debris disk 24 μm excesses on a shorter timescale than early-type stars. Simplistic Monte Carlo models suggest that, during the first Gyr of their evolution, up to 15%-30% of solar-type stars might undergo an orbital realignment of giant planets such as the one thought to have led to the Late Heavy Bombardment, if the length of the bombardment episode is similar to the one thought to have happened in our solar system. In the Appendix, we determine the cluster's parameters via bootstrap Monte Carlo isochrone fitting, yielding an age of 757 Myr (±36 Myr at 1σ confidence) and a distance of 179 pc (±2 pc at 1σ confidence), not allowing for systematic errors.
• Balog, Z., Rieke, G. H., Muzerolle, J., Bally, J., Su, K. Y., Misselt, K., & Gáspár, A. (2008). Photoevaporation of protoplanetary disks. Astrophysical Journal, 688(Issue 1). doi:10.1086/592063
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  We present HST NICMOS Paschen α (Paα) images and low- and high-resolution IRS spectra of photoevaporating disk-tail systems originally detected at 24 μm near O stars. We find no Paα emission in any of the systems. The resulting upper limits correspond to about (2-3) × 10 -6 M⊙ of mass in hydrogen in the tails, suggesting that the gas is severely depleted. The IRAC data and the low-resolution 5-12 μm IRS spectra provide evidence for an inner disk, while high-resolution long-wavelength (14-30 μm) IRS spectra confirm the presence of a gas-free tail that consists of ∼0.01 to ∼ 1 μm dust grains originating in the outer parts of the circumstellar disks. Overall, our observations support theoretical predictions in which photoevaporation removes the gas relatively quickly (≤ 105 yr) from the outer region of a protoplanetary disk, but leaves an inner, more robust, and possibly gas-rich disk component of radius 5-10 AU. With the gas gone, larger solid bodies in the outer disk can experience a high rate of collisions and produce elevated amounts of dust. This dust is being stripped from the system by the photon pressure of the O star to form a gas-free dusty tail. © 2008. The American Astronomical Society. All rights reserved.
• Balog, Z., Rieke, G., Muzerolle, J., Bally, J., Su, K., Misselt, K., & G{\'asp\'ar}, A. (2008). Photoevaporation of Protoplanetary Disks. \apj, 688, 408-417.
• G{\'asp\'ar}, A., Su, K., Rieke, G., Balog, Z., Kamp, I., Mart{\'{\i}nez-Galarza}, J., & Stapelfeldt, K. (2008). Modeling the Infrared Bow Shock at $\delta$ Velorum: Implications for Studies of Debris Disks and $\lambda$ Bo\"otis Stars. \apj, 672, 974-983.
• Gáspár, A., Su, K. Y., Rieke, G. H., Balog, Z., Kamp, I., Martínez-Galarza, J. R., & Stapelfeldt, K. (2008). Modeling the infrared bow shock at δ Velorum: Implications for studies of debris disks and λ boötis stars. Astrophysical Journal, 672(Issue 2). doi:10.1086/523299
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  We have discovered a bow shock shaped mid-infrared excess region in front of δ Velorum using 24 μm observations obtained with the Multiband Imaging Photometer for Spitzer ( MIPS). Although the bow shock morphology was only detected in the 24 μm observations, its excess was also resolved at 70 μm. We show that the stellar heating of an ambient interstellar medium (ISM) cloud can produce the measured flux. Since δ Velorum was classified as a debris disk star previously, our discovery may call into question the same classification of other stars. We model the interaction of the star and ISM, producing images that show the same geometry and surface brightness as is observed. The modeled ISM is ∼15 times overdense relative to the average Local Bubble value, which is surprising considering the close proximity (24 pc) of δ Velorum. The abundance anomalies of λ Boötis stars have been previously explained as arising from the same type of interaction of stars with the ISM. Low-resolution optical spectra of δ Velorum show that it does not belong to this stellar class. The star therefore is an interesting testbed for the ISM accretion theory of the λ Boötis phenomenon. © 2008. The American Astronomical Society. All rights reserved.
• Kamp, I., Mart{\'{\i}nez-Galarza}, J., Paunzen, E., Su, K., G{\'asp\'ar}, A., & Rieke, G. (2008). $\lambda$ Bootis stars: Current status and new insights from Spitzer. Contributions of the Astronomical Observatory Skalnate Pleso, 38, 147-156.
• Kun, M., Balog, Z., Mizuno, N., Kawamura, A., G{\'asp\'ar}, A., Kenyon, S., & Fukui, Y. (2008). Lynds 1622: a nearby star-forming cloud projected on Orion B?. \mnras, 391, 84-94.
• Lucas, P. W., Hoare, M. G., Longmore, A., Schröder, A. C., Davis, C. J., Adamson, A., Bandyopadhyay, R. M., De Grijs, R., Smith, M., Gosling, A., Mitchison, S., Gáspár, A., Coe, M., Tamura, M., Parker, Q., Irwin, M., Hambly, N., Bryant, J., Collins, R. S., , Cross, N., et al. (2008). The UKIDSS galactic plane survey. Monthly Notices of the Royal Astronomical Society, 391(Issue 1). doi:10.1111/j.1365-2966.2008.13924.x
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  The UKIDSS Galactic Plane Survey (GPS) is one of the five near-infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared Telescope. It is surveying 1868 deg2 of the northern and equatorial Galactic plane at Galactic latitudes -5° < b < 5° in the J, H and K filters and a ∼200-deg2 area of the Taurus-Auriga-Perseus molecular cloud complex in these three filters and the 2.12 μm (1-0) H2 filter. It will provide data on ∼2 × 109 sources. Here we describe the properties of the data set and provide a user's guide for its exploitation. We also present brief Demonstration Science results from DR2 and from the Science Verification programme. These results illustrate how GPS data will frequently be combined with data taken in other wavebands to produce scientific results. The Demonstration Science comprises six studies. (1) A GPS-Spitzer-GLIMPSE cross-match for the star formation region G28.983-0.603 to identify YSOs. This increases the number of YSOs identified by a factor of 10 compared to GLIMPSE alone. (2) A wide-field study of the M17 nebula, in which an extinction map of the field is presented and the effect of source confusion on luminosity functions in different subregions is noted. (3) H2 emission in the ρ Ophiuchi dark cloud. All the molecular jets are traced back to a single active clump containing only a few protostars, which suggests that the duration of strong jet activity and associated rapid accretion in low-mass protostars is brief. (4) X-ray sources in the nuclear bulge. The GPS data distinguishes local main-sequence counterparts with soft X-ray spectra from nuclear bulge giant counterparts with hard X-ray spectra. (5) External galaxies in the zone of avoidance. The galaxies are clearly distinguished from stars in fields at longitudes l > 90°. (6) IPHAS-GPS optical-infrared spectrophotometric typing. The (i′ - J) versus (J - H) diagram is used to distinguish A-F type dwarfs, G dwarfs, K dwarfs and red clump giants in a field with high reddening. © 2008 RAS.
• Lucas, P., Hoare, M., Longmore, A., Schr{\"oder}, A., Davis, C., Adamson, A., Bandyopadhyay, R., Grijs, R., Smith, M., Gosling, A., Mitchison, S., G{\'asp\'ar}, A., Coe, M., Tamura, M., Parker, Q., Irwin, M., Hambly, N., Bryant, J., Collins, R., , Cross, N., et al. (2008). The UKIDSS Galactic Plane Survey. \mnras, 391, 136-163.
• Derekas, A., Gaspar, A., & Kiss, L. L. (2007). A Variable Star Survey of the Open Cluster NGC 2126. Communications in Asteroseismology, 145, 68-68. doi:10.1553/cia145s68
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  This issue of "Communications" contains summaries of the presentations given at the minisymposium, with reviews by several selected world specialists in asteroseismology and stellar evolution, but also by young researchers, supplemented by a number of poster presentations, all of which will give the reader a broad overview of the recent status of research and highly interesting outlooks into the future.
• Kun, M., Nikoli{\'c}, S., Johansson, L., Balog, Z., & G{\'asp\'ar}, A. (2006). Low-mass star formation in Lynds 1333. \mnras, 371, 732-738.
• Vink{\'o}, J., Tak{\'ats}, K., S{\'arneczky}, K., Szab{\'o}, G., M{\'esz\'aros}, S., Csorv{\'asi}, R., Szalai, T., G{\'asp\'ar}, A., P{\'al}, A., Csizmadia, S., K{\'osp\'al}, A., R{\'acz}, M., Kun, M., Cs{\'ak}, B., F{\"ur\'esz}, G., DeBond, H., Grunhut, J., Thomson, J., Mochnacki, S., & Koktay, T. (2006). The first year of SN 2004dj in NGC 2403. \mnras, 369, 1780-1796.
• Balog, Z., Kenyon, S., Lada, E., Barsony, M., Vink{\'o}, J., & G{\'aspa\'r}, A. (2004). A Near-Infrared (JHK) Survey of the Vicinity of the H II Region NGC 7538: Evidence for a Young Embedded Cluster. \aj, 128, 2942-2953.
• Gaspar, A., Kiss, L., Derekas, A., Bedding, T., Kaspi, S., Kiss, C., Sarneczky, K., Szabo, G., & Varadi, M. (2004). A Variable Star Survey of the Open Cluster NGC 2126. Communications in Asteroseismology, 145, 70.
• G{\'asp\'ar}, A., Kiss, L., Bedding, T., Derekas, A., Kaspi, S., Kiss, C., S{\'arneczky}, K., Szab{\'o}, G., & V{\'aradi}, M. (2003). The first CCD photometric study of the open cluster NGC 2126. \aap, 410, 879-885.

Proceedings Publications

• Dicken, D., Rieke, G., Ressler, M., Morrison, J., Marin, M., Argyriou, I., Gordon, K., Regan, M., Cossou, C., Gaspar, A., Glasse, A., Guillard, P., Labiano, A., & Wright, G. (2022). Row and column artifacts in JWST MIRI's Si:As blocked impurity band detectors. In Space Telescopes and Instrumentation 2022: Optical, Infrared, and Millimeter Wave, 12180.
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  The JWST Mid-Infrared Instrument (MIRI) detector arrays are Si:As blocked impurity band devices, direct descendants of the Spitzer/IRAC long wavelength arrays. Similarly to the IRAC row-column effect, analysis of flight-like MIRI detector data has shown that columns and rows in which source signals are located can suffer from pull up (brightness increase) or pull down (brightness decrease) in the flux image. Here we present results from the JPL MIRI detector characterisation campaigns dedicated to understanding this row-column effect as well as the first results showing the effect in the flight detectors for MIRI. We show the effect is flux dependent and confirm that the effect manifests differently for rows versus columns. We discuss the origin of the flux offset, which is related to a change in the signal output in time that distorts the input ramp as a function of the saturation level of illuminated pixels. We conclude by discussing the row-column effect in the context of different MIRI instrument modes and present preliminary proposals to mitigate and/or correct the effect in MIRI data.
• Argyriou, I., Rieke, G. H., Ressler, M. E., G{'asp'ar}, A., & Vandenbussche, B. (2020, dec). "Characterization of the optical properties of the buried contact of the JWST MIRI Si: as infrared blocked impurity band detectors". In Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11454.
• Gaspar}, A., Rieke, M., Rieke, G., Leisenring, J., Ygouf, M., Beichman, C., Group, J. N., & Group, {. G. (2020, jan). "The JWST Debris Disk Spatially Resolved Imaging GTO Programs". In American Astronomical Society Meeting Abstracts #235, 235.
• Kim, D., Arenberg, J., Walker, C. K., Kim, G. H., Apai, D., Choi, H., Milster, T. D., Spires, O., Takashima, Y., Berkson, J., Schneider, G., Esparaza, M., Kim, Y., Quach, H., Fellows, C., Purvin, K., Zhang, Y., Wang, Z., Gaspar, A., , Phan, A., et al. (2020, August 2020). Disruptive space telescope concepts, designs, and developments: OASIS and Nautilus. In Topical Meeting 6 – Frontiers in Optical Metrology (EOS Annual Meeting 2020), 238 (2020), 06001.
• Grady, C., Wisniewski, J., Schneider, G., Boccaletti, A., Gaspar, A., Debes, J., Hines, D., Stark, C., Lagrange, A., Thalmann, C., Augereau, J., Milli, J., Henning, T., Sezestre, E., & Kuchner, M. (2019, jan). The Eroding Disk of the Young M Star AU Mic. In American Astronomical Society Meeting Abstracts \#233, 233.
• Su, K., Jackson, A., Gaspar, A., Dong, R., Rieke, G., Olofsson, J., & Kennedy, G. (2019, jan). Multiple Large Impacts Revealed by Disk Variability in the NGC 2547-ID8 System. In American Astronomical Society Meeting Abstracts \#233, 233.
• Ertel, S., Kennedy, G., Defr{\`ere}, D., Hinz, P., Shannon, A., Mennesson, B., Danchi, W., Gelino, C., Hill, J., Hoffman, W., Rieke, G., Spalding, E., Stone, J., Vaz, A., Weinberger, A., Willems, P., Absil, O., Arbo, P., Bailey, V., , Beichman, C., et al. (2018, jul). The HOSTS survey for exo-zodiacal dust: preliminary results and future prospects. In Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 10698.
• Kuchner, M. J., Sezestre, E., Henning, T., Milli, J., Augereay, J., Thalmann, C., Legrange, A., Stark, C., Hines, D., Debes, J., Gaspar, A., Boccaletti, A., Schneider, G., Grady, C. A., & Wisniewski, J. (2018, July). The Eroding Disk of the Young M Star AU Mic. In The 20th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun, 20, 16.
• Beichman, C., Ygouf, M., Gaspar, A., & Team, N. S. (2017, jun). NIRCam Coronagraphic Observations of Disks and Planetary Systems. In American Astronomical Society Meeting Abstracts \#230, 230.
• Meng, H., Rieke, G., Su, K., & Gaspar, A. (2017, jan). The First 40 Million Years of Circumstellar Disk Evolution: The Signature of Terrestrial Planet Formation. In American Astronomical Society Meeting Abstracts \#229, 229.
• Ballering, N., Rieke, G., Su, K., & Gaspar, A. (2016, jan). The Dust Properties of the Beta Pictoris Debris Disk from an Analysis of its Thermal Emission and Scattered Light. In American Astronomical Society Meeting Abstracts \#227, 227.
• Grady, C., Schneider, G., Carson, J., Debes, J., Gaspar, A., Henning, T., Hines, D., Hinz, P., Jang-Condell, H. .., Kuchner, M., Moro-Martin, A. .., Perrin, M., Rodigas, T., Serabyn, G., Silverstone, M., Stark, C., Tamura, M., Weinberger, A., Wisniewski, J., & Konishi, M. (2016, jan). Decoding Debris System Substructures: Imprints of Planets/Planetesimals and Signatures of Extrinsic Influences on Material in Ring-Like Disks. In American Astronomical Society Meeting Abstracts \#227, 227.
• Debes, J., Gaspar, A., Schneider, G., & Proffitt, C. (2015, nov). The HST/STIS BAR5 Occulter: High Contrast in Space at Visible Wavelengths. In AAS/Division for Planetary Sciences Meeting Abstracts \#47, 47.
• G{\'asp\'ar}, A., Rieke, G., Psaltis, D., {\"Ozel}, F., & Balog, Z. (2014, mar). The Collisional Evolution of Debris Disks. In Search for Life Beyond the Solar System. Exoplanets, Biosignatures \amp Instruments.
• Gaspar, A., Rieke, G., Psaltis, D., & Ozel, F. (2013, jan). Debris Disk Time Evolution - Connecting Observations with Theory. In American Astronomical Society Meeting Abstracts \#221, 221.
• Su, K., Rieke, G., Stapelfeldt, K., Bryden, G., Werner, M., Plavchan, P., Trilling, D., Gaspar, A., & Morales, F. (2010, jan). The Master Sample of Spitzer Debris Disk Measurements. In American Astronomical Society Meeting Abstracts \#215, 42.
• G{\'asp\'ar}, A., Balog, Z., Makai, Z., Vink{\'o}, J., & Kenyon, S. (2005, may). Preliminary Results on Newly Discovered Embedded Clusters. In Astrophysics and Space Science Library, 324.
• Derekas, A., Kiss, L., Bedding, T., G{\'asp\'ar}, A., S{\'arneczky}, K., Szab{\'o}, G., V{\'aradi}, M., Kaspi, S., & Kiss, C. (2004, may). A Variable Star Survey of the Open Cluster NGC 2126. In IAU Colloq. 193: Variable Stars in the Local Group, 310.

Others

• Schneider, G., Gaspar, A., Debes, J., Gull, T., Hines, D., Apai, D., & Rieke, G. (2019). Enabling Narrow(est) IWA Coronagraphy with STIS BAR5 and BAR10 Occulters.