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Felipe Guzman
- Professor, Optical Sciences
- Chair, Jack Lee Jewell Endowed
- Member of the Graduate Faculty
- Professor, Physics
Contact
- (520) 621-3421
- Grand Challenges Research Buil, Rm. 307
- Tucson, AZ 85719
- felipeguzman@arizona.edu
Degrees
- Ph.D. Physics
- Max Planck Institute for Gravitational Physics and Leibniz Universität Hannover, Hannover, Germany
- Gravitational wave observation from space: optical measurement techniques for LISA and LISA Pathfinder
- M.S. Engineering Physics
- Carl-von-Ossietzky Universität Oldenburg, Oldenburg, Germany
- B.S. Electrical Engineering
- Universidad de Costa Rica, San Jose, Costa Rica
Work Experience
- Texas A&M University, College Station, Texas (2020 - 2023)
- University of Arizona, Tucson, Arizona (2018 - 2020)
- DLR - German Aerospace Center (2016 - 2018)
- Joint Quantum Institute - National Institute of Standards and Technology and University of Maryland (2013 - 2016)
- Max Planck Institute for Gravitational Physics (2011 - 2012)
- NASA Goddard Space Flight Center (2009 - 2011)
Awards
- Mercator Fellow ( DFG Guest Professor)
- German Research Foundation, Winter 2024
- Jack Lee Jewell Endowed Chair in Optical Sciences
- James C. Wyant College of Optical Sciences, University of Arizona, Spring 2024
- Engineering Genesis Award
- Texas A&M, Spring 2022
- Texas A&M, Spring 2021
- Engineering Technical Achievement Award
- NASA, Spring 2021
- Mercator Fellow (DFG Guest Professor)
- German Research Foundation (DFG – Deutsche Forschungs-gemeinschaft), Summer 2019
Interests
No activities entered.
Courses
2024-25 Courses
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Optimechan Dsgn+Analysis
OPTI 523 (Spring 2025) -
Optomechan Dsgn+Analysis
OPTI 423 (Spring 2025) -
Research
ASTR 900 (Spring 2025) -
Dissertation
OPTI 920 (Fall 2024) -
Optical Dsgn+Instrumnt I
OPTI 502 (Fall 2024) -
Research
ASTR 900 (Fall 2024)
2023-24 Courses
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Directed Graduate Research
OPTI 792 (Spring 2024) -
Dissertation
OPTI 920 (Spring 2024)
2021-22 Courses
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Dissertation
OPTI 920 (Fall 2021)
2019-20 Courses
-
Research
OPTI 900 (Summer I 2020) -
Current Subj in Opti Sci
OPTI 595A (Spring 2020) -
Directed Graduate Research
OPTI 792 (Spring 2020) -
Geomet+Inst Optics II
OPTI 202R (Spring 2020) -
Independent Study
PHYS 599 (Spring 2020) -
Thesis
OPTI 910 (Spring 2020) -
Current Subj in Opti Sci
OPTI 595A (Fall 2019) -
Directed Graduate Research
OPTI 792 (Fall 2019) -
Geomet+Inst Optics I
OPTI 201R (Fall 2019) -
Independent Study
OPTI 599 (Fall 2019) -
Independent Study
PHYS 599 (Fall 2019) -
Thesis
OPTI 910 (Fall 2019)
2018-19 Courses
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Directed Research
OPTI 492 (Summer I 2019) -
Directed Graduate Research
OPTI 792 (Spring 2019) -
Independent Study
PHYS 599 (Spring 2019)
Scholarly Contributions
Journals/Publications
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2024). GWTC-2.1: Deep extended catalog of compact binary coalescences observed by LIGO and Virgo during the first half of the third observing run. Physical Review D, 109(2). doi:10.1103/PhysRevD.109.022001More infoThe second Gravitational-Wave Transient Catalog, GWTC-2, reported on 39 compact binary coalescences observed by the Advanced LIGO and Advanced Virgo detectors between 1 April 2019 15∶00 UTC and 1 October 2019 15∶00 UTC. Here, we present GWTC-2.1, which reports on a deeper list of candidate events observed over the same period. We analyze the final version of the strain data over this period with improved calibration and better subtraction of excess noise, which has been publicly released. We employ three matched-filter search pipelines for candidate identification, and estimate the probability of astrophysical origin for each candidate event. While GWTC-2 used a false alarm rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass a false alarm rate threshold of 2 per day. We calculate the source properties of a subset of 44 high-significance candidates that have a probability of astrophysical origin greater than 0.5. Of these candidates, 36 have been reported in GWTC-2. We also calculate updated source properties for all binary black hole events previously reported in GWTC-1. If the eight additional high-significance candidates presented here are astrophysical, the mass range of events that are unambiguously identified as binary black holes (both objects ≥3M⊙) is increased compared to GWTC-2, with total masses from ∼14M⊙ for GW190924_021846 to ∼182M⊙ for GW190426_190642. Source properties calculated using our default prior suggest that the primary components of two new candidate events (GW190403_051519 and GW190426_190642) fall in the mass gap predicted by pair-instability supernova theory. We also expand the population of binaries with significantly asymmetric mass ratios reported in GWTC-2 by an additional two events (the mass ratio is less than 0.65 and 0.44 at 90% probability for GW190403_051519 and GW190917_114630 respectively), and find that two of the eight new events have effective inspiral spins χeff>0 (at 90% credibility), while no binary is consistent with χeff
- Bhaskara, R. R., Majji, M., & Guzmán, F. (2024). Quantized State Estimation for Linear Dynamical Systems. Sensors, 24(19).
- Nelson, A., Sanjuan, J., & Guzmán, F. (2024). 1/f Noise Mitigation in an Opto-Mechanical Sensor with a Fabry–Pérot Interferometer. Sensors, 24(6), 1696. doi:10.3390/s24061969More infoLow-frequency and 1/f noise are common measurement limitations that arise in a variety of physical processes. Mitigation methods for these noises are dependent on their source. Here, we present a method for removing (Formula presented.) noise of optical origin using a micro-cavity Fabry–Pérot (FP) interferometer. A mechanical modulation of the FP cavity length was applied to a previously studied opto-mechanical sensor. It effectively mimics an up-conversion of the laser frequency, shifting signals to a region where lower white-noise sources dominate and (Formula presented.) noise is not present. Demodulation of this signal shifts the results back to the desired frequency range of observation with the reduced noise floor of the higher frequencies. This method was found to improve sensitivities by nearly two orders of magnitude at 1 Hz and eliminated 1/f noise in the range from 1 Hz to 4 kHz. A mathematical model for low-finesse FP cavities is presented to support these results. This study suggests a relatively simple and efficient method for (Formula presented.) noise suppression and improving the device sensitivity of systems with an FP interferometer readout.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2023). Population of Merging Compact Binaries Inferred Using Gravitational Waves through GWTC-3. Physical Review X, 13(1). doi:10.1103/PhysRevX.13.011048More infoWe report on the population properties of compact binary mergers inferred from gravitational-wave observations of these systems during the first three LIGO-Virgo observing runs. The Gravitational-Wave Transient Catalog 3 (GWTC-3) contains signals consistent with three classes of binary mergers: binary black hole, binary neutron star, and neutron star-black hole mergers. We infer the binary neutron star merger rate to be between 10 and 1700 Gpc-3 yr-1 and the neutron star-black hole merger rate to be between 7.8 and 140 Gpc-3 yr-1, assuming a constant rate density in the comoving frame and taking the union of 90% credible intervals for methods used in this work. We infer the binary black hole merger rate, allowing for evolution with redshift, to be between 17.9 and 44 Gpc-3 yr-1 at a fiducial redshift (z=0.2). The rate of binary black hole mergers is observed to increase with redshift at a rate proportional to (1+z)κ with κ=2.9-1.8+1.7 for z≲1. Using both binary neutron star and neutron star-black hole binaries, we obtain a broad, relatively flat neutron star mass distribution extending from 1.2-0.2+0.1 to 2.0-0.3+0.3M⊙. We confidently determine that the merger rate as a function of mass sharply declines after the expected maximum neutron star mass, but cannot yet confirm or rule out the existence of a lower mass gap between neutron stars and black holes. We also find the binary black hole mass distribution has localized over- and underdensities relative to a power-law distribution, with peaks emerging at chirp masses of 8.3-0.5+0.3 and 27.9-1.8+1.9M⊙. While we continue to find that the mass distribution of a binary's more massive component strongly decreases as a function of primary mass, we observe no evidence of a strongly suppressed merger rate above approximately 60M⊙, which would indicate the presence of a upper mass gap. Observed black hole spins are small, with half of spin magnitudes below χi≈0.25. While the majority of spins are preferentially aligned with the orbital angular momentum, we infer evidence of antialigned spins among the binary population. We observe an increase in spin magnitude for systems with more unequal-mass ratio. We also observe evidence of misalignment of spins relative to the orbital angular momentum.
- Hines, A., Nelson, A., Zhang, Y., Valdes, G., Sanjuan, J., & Guzman, F. (2023). Compact optomechanical accelerometers for use in gravitational wave detectors. Appl. Phys. Lett, 122(9). doi:10.1063/5.0142108More infoWe present measurements of an optomechanical accelerometer for monitoring low-frequency noise in gravitational wave detectors, such as ground motion. Our device measures accelerations by tracking the test-mass motion of a 4.7 Hz mechanical resonator using a heterodyne interferometer. This resonator is etched from monolithic fused silica, an under-explored design in low-frequency sensors, allowing a device with a noise floor competitive with existing technologies but with a lighter and more compact form. In addition, our heterodyne interferometer is a compact optical assembly that can be integrated directly into the mechanical resonator wafer to further reduce the overall size of our accelerometer. We anticipate this accelerometer to perform competitively with commercial seismometers, and benchtop measurements show a noise floor reaching 82 pico-g Hz-1/2 sensitivities at 0.4 Hz. Furthermore, we present the effects of air pressure, laser fluctuations, and temperature to determine the stability requirements needed to achieve thermally limited measurements.
- Jersey, K., Harley-Trochimczyk, I., Zhang, Y., & Guzman, F. (2023). Optical truss interferometer for the LISA telescope. Applied Optics, 62(20). doi:10.1364/ao.493108More infoThe Laser Interferometer Space Antenna telescopes must exhibit an optical path length stability of pm/√Hz in the mHz observation band to meet mission requirements. The optical truss interferometer is a proposed method to aid in the ground testing of the telescopes, as well as a risk-mitigation plan for flight units. This consists of three Fabry-Perot cavities mounted to the telescope, which are used to monitor structural displacements. We have designed and developed a fiber-based cavity injection system that integrates fiber components, mode matching optics, and a cavity input mirror into a compact input stage. The input stages, paired with return mirror stages, can be mounted to the telescope to form optical truss cavities. We performed a thorough sensitivity analysis using various simulation methods to support the fabrication and assembly of three first-generation prototype cavities, each of which exhibited satisfactory performance based on our models.
- Jersey, K., Harley-Trochimczyk, I., Zhang, Y., & Guzman, F. (2023). Optical truss interferometer for the LISA telescope. Applied Optics, 62(21), 5675. doi:10.1364/ao.493108
- Sanjuan, J., Sinyukov, A., Warrayat, M. F., & Guzman, F. (2023). Gyro-Free Inertial Navigation Systems Based on Linear Opto-Mechanical Accelerometers. Sensors, 23(8).
- Zhang, Y., Hines, A., Wilson, D., & Guzman, F. (2023). Optomechanical Cooling and Inertial Sensing at Low Frequencies. Physical Review Applied, 19(5). doi:10.1103/PhysRevApplied.19.054004More infoAn inertial sensor design is proposed in this paper to achieve high sensitivity and large dynamic range in the subhertz-frequency regime. High acceleration sensitivity is obtained by combining optical cavity readout systems with monolithically fabricated mechanical resonators. A high-sensitivity heterodyne interferometer simultaneously monitors the test mass with an extensive dynamic range for low-stiffness resonators. The bandwidth is tuned by optical feedback cooling to the test mass via radiation pressure interaction using an intensity-modulated laser. The transfer gain of the feedback system is analyzed to optimize system parameters towards the minimum cooling temperature that can be achieved. To practically implement the inertial sensor, we propose a dynamic cooling mechanism to improve cooling efficiency while operating at low optical power levels. The overall system layout presents an integrated design that is compact and lightweight.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). All-sky search for continuous gravitational waves from isolated neutron stars using Advanced LIGO and Advanced Virgo O3 data. Physical Review D, 106(10). doi:10.1103/PhysRevD.106.102008More infoWe present results of an all-sky search for continuous gravitational waves which can be produced by spinning neutron stars with an asymmetry around their rotation axis, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. Four different analysis methods are used to search in a gravitational-wave frequency band from 10 to 2048 Hz and a first frequency derivative from -10-8 to 10-9 Hz/s. No statistically significant periodic gravitational-wave signal is observed by any of the four searches. As a result, upper limits on the gravitational-wave strain amplitude h0 are calculated. The best upper limits are obtained in the frequency range of 100 to 200 Hz and they are ∼1.1×10-25 at 95% confidence level. The minimum upper limit of 1.10×10-25 is achieved at a frequency 111.5 Hz. We also place constraints on the rates and abundances of nearby planetary- and asteroid-mass primordial black holes that could give rise to continuous gravitational-wave signals.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). All-sky search for gravitational wave emission from scalar boson clouds around spinning black holes in LIGO O3 data. Physical Review Applied, 105(10). doi:10.1103/PhysRevD.105.102001More infoThis paper describes the first all-sky search for long-duration, quasimonochromatic gravitational-wave signals emitted by ultralight scalar boson clouds around spinning black holes using data from the third observing run of Advanced LIGO. We analyze the frequency range from 20 to 610 Hz, over a small frequency derivative range around zero, and use multiple frequency resolutions to be robust towards possible signal frequency wanderings. Outliers from this search are followed up using two different methods, one more suitable for nearly monochromatic signals, and the other more robust towards frequency fluctuations. We do not find any evidence for such signals and set upper limits on the signal strain amplitude, the most stringent being ≈10-25 at around 130 Hz. We interpret these upper limits as both an "exclusion region"in the boson mass/black hole mass plane and the maximum detectable distance for a given boson mass, based on an assumption of the age of the black hole/boson cloud system.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). All-sky, all-frequency directional search for persistent gravitational waves from Advanced LIGO's and Advanced Virgo's first three observing runs. Physical Review D, 105(12). doi:10.1103/PhysRevD.105.122001More infoWe present the first results from an all-sky all-frequency (ASAF) search for an anisotropic stochastic gravitational-wave background using the data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. Upper limit maps on broadband anisotropies of a persistent stochastic background were published for all observing runs of the LIGO-Virgo detectors. However, a broadband analysis is likely to miss narrowband signals as the signal-to-noise ratio of a narrowband signal can be significantly reduced when combined with detector output from other frequencies. Data folding and the computationally efficient analysis pipeline, PyStoch, enable us to perform the radiometer map-making at every frequency bin. We perform the search at 3072 HEALPix equal area pixels uniformly tiling the sky and in every frequency bin of width 1/32 Hz in the range 20-1726 Hz, except for bins that are likely to contain instrumental artefacts and hence are notched. We do not find any statistically significant evidence for the existence of narrowband gravitational-wave signals in the analyzed frequency bins. Therefore, we place 95% confidence upper limits on the gravitational-wave strain for each pixel-frequency pair, the limits are in the range (0.030-9.6)×10-24. In addition, we outline a method to identify candidate pixel-frequency pairs that could be followed up by a more sensitive (and potentially computationally expensive) search, e.g., a matched-filtering-based analysis, to look for fainter nearly monochromatic coherent signals. The ASAF analysis is inherently independent of models describing any spectral or spatial distribution of power. We demonstrate that the ASAF results can be appropriately combined over frequencies and sky directions to successfully recover the broadband directional and isotropic results.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). Constraints on dark photon dark matter using data from LIGO's and Virgo's third observing run. Physical Review Applied, 105(6). doi:10.1103/PhysRevD.105.063030More infoWe present a search for dark photon dark matter that could couple to gravitational-wave interferometers using data from Advanced LIGO and Virgo's third observing run. To perform this analysis, we use two methods, one based on cross-correlation of the strain channels in the two nearly aligned LIGO detectors, and one that looks for excess power in the strain channels of the LIGO and Virgo detectors. The excess power method optimizes the Fourier transform coherence time as a function of frequency, to account for the expected signal width due to Doppler modulations. We do not find any evidence of dark photon dark matter with a mass between mA∼10-14-10-11 eV/c2, which corresponds to frequencies between 10-2000 Hz, and therefore provide upper limits on the square of the minimum coupling of dark photons to baryons, i.e., U(1)B dark matter. For the cross-correlation method, the best median constraint on the squared coupling is ∼1.31×10-47 at mA∼4.2×10-13 eV/c2; for the other analysis, the best constraint is ∼2.4×10-47 at mA∼5.7×10-13 eV/c2. These limits improve upon those obtained in direct dark matter detection experiments by a factor of ∼100 for mA∼[2-4]×10-13 eV/c2, and are, in absolute terms, the most stringent constraint so far in a large mass range mA∼2×10-13-8×10-12 eV/c2.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). First joint observation by the underground gravitational-wave detector KAGRA with GEO 600. Progress of Theor. and Exp. Phys., 2022(6). doi:10.1093/ptep/ptac073More infoWe report the results of the first joint observation of the KAGRA detector with GEO 600. KAGRA is a cryogenic and underground gravitational-wave detector consisting of a laser interferometer with 3 km arms, located in Kamioka, Gifu, Japan. GEO 600 is a British-German laser interferometer with 600 m arms, located near Hannover, Germany. GEO 600 and KAGRA performed a joint observing run from April 7 to 20, 2020. We present the results of the joint analysis of the GEO-KAGRA data for transient gravitational-wave signals, including the coalescence of neutron-star binaries and generic unmodeled transients. We also perform dedicated searches for binary coalescence signals and generic transients associated with gamma-ray burst events observed during the joint run. No gravitational-wave events were identified. We evaluate the minimum detectable amplitude for various types of transient signals and the spacetime volume for which the network is sensitive to binary neutron-star coalescences. We also place lower limits on the distances to the gamma-ray bursts analyzed based on the non-detection of an associated gravitational-wave signal for several signal models, including binary coalescences. These analyses demonstrate the feasibility and utility of KAGRA as a member of the global gravitational-wave detector network.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). First joint observation by the underground gravitational-wave detector KAGRA with GEO 600. Progress of Theor. and Exp. Phys, 2022(6). doi:10.1093/ptep/ptac073More infoWe report the results of the first joint observation of the KAGRA detector with GEO 600. KAGRA is a cryogenic and underground gravitational-wave detector consisting of a laser interferometer with 3 km arms, located in Kamioka, Gifu, Japan. GEO 600 is a British-German laser interferometer with 600 m arms, located near Hannover, Germany. GEO 600 and KAGRA performed a joint observing run from April 7 to 20, 2020. We present the results of the joint analysis of the GEO-KAGRA data for transient gravitational-wave signals, including the coalescence of neutron-star binaries and generic unmodeled transients. We also perform dedicated searches for binary coalescence signals and generic transients associated with gamma-ray burst events observed during the joint run. No gravitational-wave events were identified. We evaluate the minimum detectable amplitude for various types of transient signals and the spacetime volume for which the network is sensitive to binary neutron-star coalescences. We also place lower limits on the distances to the gamma-ray bursts analyzed based on the non-detection of an associated gravitational-wave signal for several signal models, including binary coalescences. These analyses demonstrate the feasibility and utility of KAGRA as a member of the global gravitational-wave detector network.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2022). Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run. Astrophysical Journal, 932(2). doi:10.3847/1538-4357/ac6ad0More infoIsolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets.
- Armano, M., Audley, H., Baird, J., Binetruy, P., Born, M., Bortoluzzi, D., Brandt, N., Castelli, E., Cavalleri, A., Cesarini, A., Cruise, A., Danzmann, K., De Deus Silva, M., Diepholz, I., Dixon, G., Dolesi, R., Ferraioli, L., Ferroni, V., Fitzsimons, E., , Flatscher, R., et al. (2022). Sensor noise in LISA Pathfinder: An extensive in-flight review of the angular and longitudinal interferometric measurement system. Physical Review Applied, 106(8). doi:10.1103/PhysRevD.106.082001More infoIn a previous article [1], we have reported on the first subpicometer interferometer flown in space as part of ESA's LISA Pathfinder mission, and have shown the residual sensor noise to be on the level of 32.0-1.7+2.4 fm/Hz. This review provides a deeper and more complete overview of the full system and its interferometric mission performance under varying operational conditions, allowing a much more detailed view on the noise model. We also include the optical measurements of rotations through differential wave front sensing (DWS), which reached a sensitivity of as good as 100 prad/Hz. We present more evidence for the long-term stability of the interferometric performance and components. This proves a solid foundation for future interferometry in space such as the LISA mission.
- Valdes, G., Hines, A., Nelson, A., Zhang, Y., & Guzman, F. (2022). A characterization method for low-frequency seismic noise in LIGO. Appl. Phys. Lett, 121(23). doi:10.1063/5.0122495More infoWe present a method to characterize the noise in ground-based gravitational-wave observatories such as the Laser Gravitational-Wave Observatory (LIGO). This method uses linear regression algorithms such as the least absolute shrinkage and selection operator to identify noise sources and analyzes the detector output vs noise witness sensors to quantify the coupling of such noise. Our method can be implemented with currently available resources at LIGO, which avoids extra coding or direct experimentation at the LIGO sites. We present two examples to validate and estimate the coupling of elevated ground motion at frequencies below 10 Hz with noise in the detector output.
- Zhang, Y., & Guzman, F. (2022). Fiber-based two-wavelength heterodyne laser interferometer. Optics Express, 30(21). doi:10.1364/OE.466332More infoDisplacement measuring interferometry is a crucial component in metrology applications. In this paper, we propose a fiber-based two-wavelength heterodyne interferometer as a compact and highly sensitive displacement sensor that can be used in inertial sensing applications. In the proposed design, two individual heterodyne interferometers are constructed using two different wavelengths, 1064 nm and 1055 nm; one of which measures the target displacement and the other monitors the common-mode noise in the fiber system. A narrow-bandwidth spectral filter separates the beam paths of the two interferometers, which are highly common and provide a high rejection ratio to the environmental noise. The preliminary test shows a sensitivity floor of 7.5pm/√Hz at 1 Hz when tested in an enclosed chamber. We also investigated the effects of periodic errors due to imperfect spectral separation on the displacement measurement and propose algorithms to mitigate these effects.
- Zhang, Y., & Guzman, F. (2022). Quasi-monolithic heterodyne laser interferometer for inertial sensing. Optics Letters, 47(19), 5120-5123. doi:10.1364/OL.473476More infoWe present a compact heterodyne laser interferometer developed for high-sensitivity displacement sensing applications. This interferometer consists of customized prisms and wave plates assembled as a quasi-monolithic unit to realize a miniaturized system. The interferometer design adopts a common-mode rejection scheme to provide a high rejection ratio to common environmental noise. Experimental tests in vacuum show a displacement sensitivity level of 11 pm/√Hz at 100 mHz and as low as 0.6 pm/√Hz above 1 pm. The prototype unit is 20 mm × 20 mm × 10 mm in size and weighs 4.5 g, allowing subsequent integration in compact systems.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). All-sky search for long-duration gravitational-wave bursts in the third Advanced LIGO and Advanced Virgo run. Phys Rev D, 104(10). doi:10.1103/PhysRevD.104.102001More infoAfter the detection of gravitational waves from compact binary coalescences, the search for transient gravitational-wave signals with less well-defined waveforms for which matched filtering is not well suited is one of the frontiers for gravitational-wave astronomy. Broadly classified into "short"1 s and "long"1 s duration signals, these signals are expected from a variety of astrophysical processes, including non-axisymmetric deformations in magnetars or eccentric binary black hole coalescences. In this work, we present a search for long-duration gravitational-wave transients from Advanced LIGO and Advanced Virgo's third observing run from April 2019 to March 2020. For this search, we use minimal assumptions for the sky location, event time, waveform morphology, and duration of the source. The search covers the range of 2-500 s in duration and a frequency band of 24-2048 Hz. We find no significant triggers within this parameter space; we report sensitivity limits on the signal strength of gravitational waves characterized by the root-sum-square amplitude hrss as a function of waveform morphology. These hrss limits improve upon the results from the second observing run by an average factor of 1.8.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). All-sky search for short gravitational-wave bursts in the third Advanced LIGO and Advanced Virgo run. Phys. Rev. D., 104(12). doi:10.1103/PhysRevD.104.122004More infoThis paper presents the results of a search for generic short-duration gravitational-wave transients in data from the third observing run of Advanced LIGO and Advanced Virgo. Transients with durations of milliseconds to a few seconds in the 24-4096 Hz frequency band are targeted by the search, with no assumptions made regarding the incoming signal direction, polarization, or morphology. Gravitational waves from compact binary coalescences that have been identified by other targeted analyses are detected, but no statistically significant evidence for other gravitational wave bursts is found. Sensitivities to a variety of signals are presented. These include updated upper limits on the source rate density as a function of the characteristic frequency of the signal, which are roughly an order of magnitude better than previous upper limits. This search is sensitive to sources radiating as little as ∼10-10 Mc2 in gravitational waves at ∼70 Hz from a distance of 10 kpc, with 50% detection efficiency at a false alarm rate of one per century. The sensitivity of this search to two plausible astrophysical sources is estimated: neutron star f modes, which may be excited by pulsar glitches, as well as selected core-collapse supernova models.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). Constraints from LIGO O3 Data on Gravitational-wave Emission Due to R-modes in the Glitching Pulsar PSR J0537-6910. The Astrophysical Journal, 922(1). doi:10.3847/1538-4357/ac0d52More infoWe present a search for continuous gravitational-wave emission due to r-modes in the pulsar PSR J0537-6910 using data from the LIGO-Virgo Collaboration observing run O3. PSR J0537-6910 is a young energetic X-ray pulsar and is the most frequent glitcher known. The inter-glitch braking index of the pulsar suggests that gravitational-wave emission due to r-mode oscillations may play an important role in the spin evolution of this pulsar. Theoretical models confirm this possibility and predict emission at a level that can be probed by ground-based detectors. In order to explore this scenario, we search for r-mode emission in the epochs between glitches by using a contemporaneous timing ephemeris obtained from NICER data. We do not detect any signals in the theoretically expected band of 86-97 Hz, and report upper limits on the amplitude of the gravitational waves. Our results improve on previous amplitude upper limits from r-modes in J0537-6910 by a factor of up to 3 and place stringent constraints on theoretical models for r-mode-driven spin-down in PSR J0537-6910, especially for higher frequencies at which our results reach below the spin-down limit defined by energy conservation.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run. Physical Review Applied, 126(24). doi:10.1103/PhysRevLett.126.241102More infoWe search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10-15. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). Diving below the Spin-down Limit: Constraints on Gravitational Waves from the Energetic Young Pulsar PSR J0537-6910. Astrophysical Journal Letters, 913(2). doi:10.3847/2041-8213/abffcdMore infoWe present a search for quasi-monochromatic gravitational-wave signals from the young, energetic X-ray pulsar PSR J0537-6910 using data from the second and third observing runs of LIGO and Virgo. The search is enabled by a contemporaneous timing ephemeris obtained using Neutron star Interior Composition Explorer (NICER) data. The NICER ephemeris has also been extended through 2020 October and includes three new glitches. PSR J0537-6910 has the largest spin-down luminosity of any pulsar and exhibits fRequent and strong glitches. Analyses of its long-term and interglitch braking indices provide intriguing evidence that its spin-down energy budget may include gravitational-wave emission from a time-varying mass quadrupole moment. Its 62 Hz rotation frequency also puts its possible gravitational-wave emission in the most sensitive band of the LIGO/Virgo detectors. Motivated by these considerations, we search for gravitational-wave emission at both once and twice the rotation frequency from PSR J0537-6910. We find no signal, however, and report upper limits. Assuming a rigidly rotating triaxial star, our constraints reach below the gravitational-wave spin-down limit for this star for the first time by more than a factor of 2 and limit gravitational waves from the l = m = 2 mode to account for less than 14% of the spin-down energy budget. The fiducial equatorial ellipticity is constrained to less than about 3 ×10-5, which is the third best constraint for any young pulsar.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). GWTC-2: Compact Binary Coalescences Observed by LIGO and Virgo during the First Half of the Third Observing Run. Phys. Rev. X, 11(2). doi:10.1103/PhysRevX.11.021053More infoWe report on gravitational-wave discoveries from compact binary coalescences detected by Advanced LIGO and Advanced Virgo in the first half of the third observing run (O3a) between 1 April 2019 15:00 UTC and 1 October 2019 15:00 UTC. By imposing a false-alarm-rate threshold of two per year in each of the four search pipelines that constitute our search, we present 39 candidate gravitational-wave events. At this threshold, we expect a contamination fraction of less than 10%. Of these, 26 candidate events were reported previously in near-real time through gamma-ray coordinates network notices and circulars; 13 are reported here for the first time. The catalog contains events whose sources are black hole binary mergers up to a redshift of approximately 0.8, as well as events whose components cannot be unambiguously identified as black holes or neutron stars. For the latter group, we are unable to determine the nature based on estimates of the component masses and spins from gravitational-wave data alone. The range of candidate event masses which are unambiguously identified as binary black holes (both objects ≥3 Mo˙) is increased compared to GWTC-1, with total masses from approximately 14 Mo˙ for GW190924_021846 to approximately 150 Mo˙ for GW190521. For the first time, this catalog includes binary systems with significantly asymmetric mass ratios, which had not been observed in data taken before April 2019. We also find that 11 of the 39 events detected since April 2019 have positive effective inspiral spins under our default prior (at 90% credibility), while none exhibit negative effective inspiral spin. Given the increased sensitivity of Advanced LIGO and Advanced Virgo, the detection of 39 candidate events in approximately 26 weeks of data (approximately 1.5 per week) is consistent with GWTC-1.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). Observation of Gravitational Waves from Two Neutron Star-Black Hole Coalescences. Astrophysical Journal Letters, 915(1). doi:10.3847/2041-8213/ac082eMore infoWe report the observation of gravitational waves from two compact binary coalescences in LIGO's and Virgo's third observing run with properties consistent with neutron star-black hole (NSBH) binaries. The two events are named GW200105_162426 and GW200115_042309, abbreviated as GW200105 and GW200115; the first was observed by LIGO Livingston and Virgo and the second by all three LIGO-Virgo detectors. The source of GW200105 has component masses, whereas the source of GW200115 has component masses and (all measurements quoted at the 90% credible level). The probability that the secondary's mass is below the maximal mass of a neutron star is 89%-96% and 87%-98%, respectively, for GW200105 and GW200115, with the ranges arising from different astrophysical assumptions. The source luminosity distances are and, respectively. The magnitude of the primary spin of GW200105 is less than 0.23 at the 90% credible level, and its orientation is unconstrained. For GW200115, the primary spin has a negative spin projection onto the orbital angular momentum at 88% probability. We are unable to constrain the spin or tidal deformation of the secondary component for either event. We infer an NSBH merger rate density of when assuming that GW200105 and GW200115 are representative of the NSBH population or under the assumption of a broader distribution of component masses.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2021). Search for Lensing Signatures in the Gravitational-Wave Observations from the First Half of LIGO-Virgo's Third Observing Run. ApJ, 923(1). doi:10.3847/1538-4357/ac23dbMore infoWe search for signatures of gravitational lensing in the gravitational-wave signals from compact binary coalescences detected by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) and Advanced Virgo during O3a, the first half of their third observing run. We study: (1) the expected rate of lensing at current detector sensitivity and the implications of a non-observation of strong lensing or a stochastic gravitational-wave background on the merger-rate density at high redshift; (2) how the interpretation of individual high-mass events would change if they were found to be lensed; (3) the possibility of multiple images due to strong lensing by galaxies or galaxy clusters; and (4) possible wave-optics effects due to point-mass microlenses. Several pairs of signals in the multiple-image analysis show similar parameters and, in this sense, are nominally consistent with the strong lensing hypothesis. However, taking into account population priors, selection effects, and the prior odds against lensing, these events do not provide sufficient evidence for lensing. Overall, we find no compelling evidence for lensing in the observed gravitational-wave signals from any of these analyses.
- Armano, M., Audley, H., Baird, J., Binetruy, P., Born, M., Bortoluzzi, D., Brandt, N., Castelli, E., Cavalleri, A., Cesarini, A., Cruise, A., Danzmann, K., De Deus Silva, M., Diepholz, I., Dixon, G., Dolesi, R., Ferraioli, L., Ferroni, V., Fitzsimons, E., , Flatscher, R., et al. (2021). Sensor Noise in LISA Pathfinder: In-Flight Performance of the Optical Test Mass Readout. Physical Review Letters, 126(13). doi:10.1103/PhysRevLett.126.131103More infoWe report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0-1.7+2.4 fm/Hz, significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.
- Kelly, P., Majji, M., & Guzmán, F. (2021). Estimation and error analysis for optomechanical inertial sensors. Sensors 21, 21(18). doi:10.3390/s21186101More infoA sensor model and methodology to estimate the forcing accelerations measured using a novel optomechanical inertial sensor with the inclusion of stochastic bias and measurement noise processes is presented. A Kalman filter for the estimation of instantaneous sensor bias is developed; the outputs from this calibration step are then employed in two different approaches for the estimation of external accelerations applied to the sensor. The performance of the system is demonstrated using simulated measurements and representative values corresponding to a bench-tested 3.76 Hz oscillator. It is shown that the developed methods produce accurate estimates of the bias over a short calibration step. This information enables precise estimates of acceleration over an extended operation period. These results establish the feasibility of reliably precise acceleration estimates using the presented methods in conjunction with state of the art optomechanical sensing technology.
- Zhang, Y., Hines, A., Valdes, G., & Guzman, F. (2021). Investigation and mitigation of noise contributions in a compact heterodyne interferometer. Sensors, 21(17), 5788. doi:10.3390/s21175788More infoWe present a noise estimation and subtraction algorithm capable of increasing the sensitivity of heterodyne laser interferometers by one order of magnitude. The heterodyne interferometer is specially designed for dynamic measurements of a test mass in the application of sub-Hz inertial sensing. A noise floor of 3.31 × 10−11 m/√Hz at 100 mHz is achieved after applying our noise subtraction algorithm to a benchtop prototype interferometer that showed a noise level of 2.76 × 10−10 m/√Hz at 100 mHz when tested in vacuum at levels of 3 × 10−5 Torr. Based on the previous results, we investigated noise estimation and subtraction techniques of non-linear optical pathlength noise, laser frequency noise, and temperature fluctuations in heterodyne laser interferometers. For each noise source, we identified its contribution and removed it from the measurement by linear fitting or a spectral analysis algorithm. The noise correction algorithm we present in this article can be generally applied to heterodyne laser interferometers.
- , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , ., , , ., et al. (2020). Gravitational-wave Constraints on the Equatorial Ellipticity of Millisecond Pulsars. Astrophysical Journal Letters, 902(1). doi:10.3847/2041-8213/abb655More infoWe present a search for continuous gravitational waves from five radio pulsars, comprising three recycled pulsars (PSR J0437-4715, PSR J0711-6830, and PSR J0737-3039A) and two young pulsars: the Crab pulsar (J0534+2200) and the Vela pulsar (J0835-4510). We use data from the third observing run of Advanced LIGO and Virgo combined with data from their first and second observing runs. For the first time, we are able to match (for PSR J0437-4715) or surpass (for PSR J0711-6830) the indirect limits on gravitational-wave emission from recycled pulsars inferred from their observed spin-downs, and constrain their equatorial ellipticities to be less than 10-8. For each of the five pulsars, we perform targeted searches that assume a tight coupling between the gravitational-wave and electromagnetic signal phase evolution. We also present constraints on PSR J0711-6830, the Crab pulsar, and the Vela pulsar from a search that relaxes this assumption, allowing the gravitational-wave signal to vary from the electromagnetic expectation within a narrow band of frequencies and frequency derivatives.
- Guzman, F., Hines, A. S., Richardson, L., & Wisniewski, H. (2020). Optomechanical inertial sensors.. Applied optics, 59(22), G167-G174. doi:10.1364/ao.393061More infoWe present a performance analysis of compact monolithic optomechanical inertial sensors that describes their key fundamental limits and overall acceleration noise floor. Performance simulations for low-frequency gravity-sensitive inertial sensors show attainable acceleration noise floors on the order of 1×10-11m/s2Hz. Furthermore, from our performance models, we devised an optimization approach for our sensor designs, sensitivity, and bandwidth trade space. We conducted characterization measurements of these compact mechanical resonators, demonstrating mQ-products at levels of 250 kg, which highlight their exquisite acceleration sensitivity.
- Hines, A., Richardson, L., Wisniewski, H., & Guzman, F. (2020). Optomechanical inertial sensors. Applied Optics, 59(22). doi:10.1364/AO.393061More infoWe present a performance analysis of compact monolithic optomechanical inertial sensors that describes their key fundamental limits and overall acceleration noise floor. Performance simulations for low-frequency gravity-sensitive inertial sensors show attainable acceleration noise floors on the order of 1 × 10−11 m/s2√Hz. Furthermore, from our performance models, we devised an optimization approach for our sensor designs, sensitivity, and bandwidth trade space. We conducted characterization measurements of these compact mechanical resonators, demonstrating mQ-products at levels of 250 kg, which highlight their exquisite acceleration sensitivity.
- Joo, K., Clark, E., Zhang, Y., Ellis, J., & Guzman, F. (2020). A compact high-precision periodic-error-free heterodyne interferometer. Journal of the Optical Society of America, 37(9), B11-B18. doi:10.1364/JOSAA.396298More infoWe present the design, bench-top setup, and experimental results of a compact heterodyne interferometer that achieves picometer-level displacement sensitivities in air over frequencies above 100 MHz. The optical configuration with spatially separated beams prevents frequency and polarization mixing, and therefore eliminates periodic errors. The interferometer is designed to maximize common-mode optical laser beam paths to obtain high rejection of environmental disturbances, such as temperature fluctuations and acoustics. The results of our experiments demonstrate the short- and long-term stabilities of the system during stationary and dynamic measurements. In addition, we provide measurements that compare our interferometer prototype with a commercial system, verifying our higher sensitivity of 3 pm, higher thermal stability by a factor of two, and periodic-error-free performance.
- Richardson, L., Hines, A., Schaffer, A., Anderson, B. P., & Guzman, F. (2020). Quantum hybrid optomechanical inertial sensing. Applied Optics, 59(22), G160.
- Richardson, L., Rajagopalan, A., Albers, H., Meiners, C., Nath, D., Schubert, C., Tell, D., Wodey, É., Abend, S., Gersemann, M., Ertmer, W., Rasel, E., Schlippert, D., Mehmet, M., Kumanchik, L., Colmenero, L., Spannagel, R., Braxmaier, C., & Guzmán, F. (2020). Optomechanical resonator-enhanced atom interferometry. Communications Physics, 3(1). doi:10.1038/s42005-020-00473-4More infoMatter-wave interferometry and spectroscopy of optomechanical resonators offer complementary advantages. Interferometry with cold atoms is employed for accurate and long-term stable measurements, yet it is challenged by its dynamic range and cyclic acquisition. Spectroscopy of optomechanical resonators features continuous signals with large dynamic range, however it is generally subject to drifts. In this work, we combine the advantages of both devices. Measuring the motion of a mirror and matter waves interferometrically with respect to a joint reference allows us to operate an atomic gravimeter in a seismically noisy environment otherwise inhibiting readout of its phase. Our method is applicable to a variety of quantum sensors and shows large potential for improvements of both elements by quantum engineering.
- Wisniewski, H., Richardson, L., Hines, A., Laurain, A., & Guzmán, F. (2020). Optomechanical lasers for inertial sensing. Journal of the Optical Society of America A: Optics and Image Science, and Vision, 37(9). doi:10.1364/JOSAA.396774More infoWe have developed an inertially sensitive optomechanical laser by combining a vertical-external-cavity surface-emitting laser (VECSEL) with a monolithic fused silica resonator. By placing the external cavity mirror of the VECSEL onto the optomechanical resonator test mass, we create a sensor where external accelerations are directly transcribed onto the lasing frequency. We developed a proof-of-principle laboratory prototype and observe test mass oscillations at the resonance frequency of the sensor through the VECSEL lasing frequency, 4.18 ± 0.03 Hz. In addition, we set up an ancillary heterodyne interferometer to track the motion of the mechanical oscillator’s test mass, observing a resonance of 4.194 ± 0.004 Hz. The interferometer measurements validate the VECSEL results, confirming the feasibility of using optomechanical lasers for inertial sensing. © 2020 Optical Society of America
- Hamann, I., Sanjuan, J., Spannagel, R., Gohlke, M., Wanner, G., Schuster, S., Guzman, F., & Braxmaier, C. (2019). Laser-dilatometer calibration using a single-crystal silicon sample. International Journal of Optomechanatronics, 13(1). doi:10.1080/15599612.2019.1587117More infoMarginal changes in geometrical dimensions due to temperature changes affect the performance of optical instruments. Highly dimensionally stable materials can minimize these effects since they offer low coefficients of thermal expansion (CTE). Our dilatometer, based on heterodyne interferometry, is able to determine the CTE in 10-8 K-1 range. Here, we present the improved interferometer performance using angular measurements via differential wavefront sensing to correct for tilt-to-length coupling. The setup was tested by measuring the CTE of a single-crystal silicon at 285 K. Results are in good agreement with the reported values and show a bias of less than 1%.
- Lundquist, M., Paterson, K., Fong, W., Sand, D., Andrews, J., Shivaei, I., Daly, P., Valenti, S., Yang, S., Christensen, E., Gibbs, A., Shelly, F., Wyatt, S., Eskandari, O., Kuhn, O., Amaro, R., Arcavi, I., Behroozi, P., Butler, N., , Chomiuk, L., et al. (2019). Searches after Gravitational Waves Using ARizona Observatories (SAGUARO): System Overview and First Results from Advanced LIGO/Virgo's Third Observing Run. Astrophysical Journal Letters, 881(2). doi:10.3847/2041-8213/ab32f2More infoWe present Searches After Gravitational-waves Using ARizona Observatories (SAGUARO), a comprehensive effort dedicated to the discovery and characterization of optical counterparts to gravitational-wave (GW) events. SAGUARO utilizes ground-based facilities ranging from 1.5 to 10 m in diameter, located primarily in the Northern Hemisphere. We provide an overview of SAGUARO's telescopic resources, its pipeline for transient detection, and its database for candidate visualization. We describe SAGUARO's discovery component, which utilizes the 5deg2 field of view optical imager on the Mt. Lemmon 1.5 m telescope, reaching limits of ≈21.3 AB mag while rapidly tiling large areas. We also describe the follow-up component of SAGUARO, used for rapid vetting and monitoring of optical candidates. With the onset of Advanced LIGO/Virgo's third observing run, we present results from the first three SAGUARO searches following the GW events S190408an, S190425z and S190426c, which serve as a valuable proof-of-concept of SAGUARO. We triggered and searched 15, 60, and 60 deg2 respectively, 17.6, 1.4, and 41.8 hr after the initial GW alerts. We covered 7.8%, 3.0%, and 5.1% of the total probability within the GW event localizations, reaching 3σ limits of 19.8, 21.3, and 20.8 AB mag, respectively. Although no viable counterparts associated with these events were found, we recovered six known transients and ruled out five potential candidates. We also present Large Binocular Telescope spectroscopy of PS19eq/SN2019ebq, a promising kilonova candidate that was later determined to be a supernova. With the ability to tile large areas and conduct detailed follow-up, SAGUARO represents a significant addition to GW counterpart searches.
- Ryan, W. (2018). Towards a photonic quantum standard for mass and force. IEEE Conference on Precision Electromagnetic Measurements (CPEM).
- Wagner, R., Guzman, F., Chijioke, A., Gulati, G., Keller, M., & Shaw, G. (2018). Direct measurement of radiation pressure and circulating power inside a passive optical cavity. Optics Express, 26(18). doi:10.1364/OE.26.023492More infoA mechanical force sensor coupled to two optical cavities is developed as a metrological tool. This system is used to generate a calibrated circulating optical power and to create a transfer standard for externally coupled optical power. The variability of the sensor as a transfer standard for optical power is less than 2%. The uncertainty in using the sensor to measure the circulating power inside the cavity is less than 3%. The force measured from the mechanical response of the sensor is compared to the force predicted from characterizing the optical spectrum of the cavity. These two forces are approximately 20% different. Potential sources for this disagreement are analyzed and discussed. The sensor is compact, portable, and can operate in ambient and vacuum environments. This device provides a pathway to novel nanonewton scale force and milliwatt scale laser power calibrations, enables direct measurement of the circulating power inside an optical cavity, and enhances the sensitivity of radiation pressure-based optical power transfer standards.
- Armano, M., Audley, H., Auger, G., Baird, J. T., Bassan, M., Binetruy, P., Born, M., Bortoluzzi, D., Brandt, N., Caleno, M., Carbone, L., Cavalleri, A., Cesarini, A., Ciani, G., Congedo, G., Cruise, A. M., Danzmann, K., Deus Silva, M., De Rosa, R., , Diaz-Aguil\'o, M., et al. (2016). Sub-Femto-$g$ Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results. Phys. Rev. Lett., 116, 231101.
- Gordon, A. (2016). Using small mass and force metrology for laser power measurement. IEEE Conference on Precision Electromagnetic Measurements (CPEM).
- Katharina-Sofie, I. (2016). Experimental demonstration of deep frequency modulation interferometry. Optics Express, 24(2), 1676--1684.
- Yiliang, B. (2016). An optomechanical accelerometer with a high-finesse hemispherical optical cavity. IEEE International Symposium on Inertial Sensors and Systems.
- Ferran, G., & Danzmann, K. (2015). Thermo-elastic induced phase noise in the LISA Pathfinder spacecraft. Classical and Quantum Gravity, 32.
- Guzm\'an, C. (2015). MEMS optomechanical accelerometry standards. American Society of Precision Engineering, Conference on Precision Interferometry.
- Guzm\'an, C., & Taylor, J. M. (2015). Optomechanical motion sensors. American Society of Precision Engineering, Conference on Precision Interferometry.
- M., T. (2015). Towards a FPGA-controlled deep phase modulation interferometer. Journal of Physics: Conference Series, 610, 012042.
- Oliver, G. (2015). Optomechanical reference accelerometer. Metrologia, 52.
- Guzm\'an, C. (2014). High sensitivity optomechanical reference accelerometer over 10 kHz. Applied Physics Letters, 104.
- Melcher, J., Stirling, J., Cervantes, ., Pratt, J., & Shaw, G. (2014). A self-calibrating optomechanical force sensor with femtonewton resolution. Applied Physics Letters, 105.
- Schwarze, T., Gerberding, O., Cervantes, ., Heinzel, G., & Danzmann, K. (2014). Advanced phasemeter for deep phase modulation interferometry. Optics Express, 22.
- Yicheng, W. (2014). Alignment and testing of the NIST Calculable Capacitor. IEEE CPEM 2014, Conference on Precision Electromagnetic Measurements.
- Cervantes, F., Flatscher, R., Gerardi, D., Burkhardt, J., Gerndt, R., Nofrarias, M., Reiche, J., Heinzel, G., Danzmann, K., Bot\'e, L., Mart\'in, V., Mateos, I., & Lobo, A. (2013). LISA Technology Package Flight Hardware Test Campaign. Astronomical Society of the Pacific Conference Series, 467, 141.
- M, N., & Zweifel, P. (2013). State Space Modelling and Data Analysis Exercises in LISA Pathfinder. Astronomical Society of the Pacific Conference Series, 467, 161.
- F, A. (2012). The LISA Pathfinder Mission. Classical and Quantum Gravity, 29(12), 124014.
- Joshi, A., Datta, S., Rue, J., Livas, J., Silverberg, R., & Cervantes, F. (2012). Ultra-Low Noise, Large-Area InGaAs Quad Photoreceiver with Low Crosstalk for Laser Interferometry Space Antenna. SPIE Astronomical Telescopes and Instrumentation, 84532G--84532G.
- Audley, H., Danzmann, K., Mar\'in, A. G., Heinzel, G., Monsky, A., Nofrarias, M., Steier, F., Gerardi, D., Gerndt, R., Hechenblaikner, G., Johann, U., Luetzow-Wentzky, P., Wand, V., Antonucci, F., Armano, M., Auger, G., Benedetti, M., Binetruy, P., Boatella, C., , Bogenstahl, J., et al. (2011). The LISA Pathfinder interferometry - hardware and system testing. Class. Quantum Grav., 28(9), 094003.
- Esteban, J. J., Garc\'ia, A. F., Barke, S., Peinado, A. M., Cervantes}, ., Bykov, I., Heinzel, G., & Danzmann, K. (2011). Experimental demonstration of weak-light laser ranging and data communication for LISA. Optics Express, 19(17), 15937--15946.
- F., A. (2011). From laboratory experiments to LISA Pathfinder: achieving LISA geodesic motion.. Class. Quantum Grav., 28(9), 094002.
- F., A. (2011). LISA Pathfinder Data Analysis. Class. Quantum Grav., 28(9), 094006.
- F., A. (2011). LISA Pathfinder: mission and status. Class. Quantum Grav., 28(9), 094001.
- Guzm\'an, C. (2011). Characterization of photoreceivers for LISA. Classical and Quantum Gravity, 28(9), 094010.
- Gerhard, H. (2010). Deep phase modulation interferometry. Opt. Express, 18(18), 19076--19086.
- A., M., & Zweifel, P. (2009). The first mock data challenge for LISA Pathfinder. Class. Quantum Grav., 26.
- F., S., & Danzmann, K. (2009). The end-to-end testbed of the optical metrology system on-board LISA Pathfinder. Class. Quantum Grav., 26.
- M, A., & Zweifel, P. (2009). LISA Pathfinder: the experiment and the route to LISA. Class. Quantum Grav., 26.
- M., H., & Zweifel, P. (2009). Data analysis for the LISA Technology Package. Class. Quantum Grav., 26.
- Marina, D., & Danzmann, K. (2009). Laser interferometer for spaceborne mapping of the Earth's gravity field. J. Phys.: Conf. Ser., 154.
- Guzm\'an, C. (2008). Subtraction of test mass angular noise in the LISA technology package interferometer. Applied Physics B, 90.
- Guzm\'an, C., & Danzmann, K. (2007). Real-time phasefront detector for heterodyne interferometers. Applied Optics, 46.
- A., G. M., & Danzmann, K. (2006). Interferometric characterization of the optical window for LISA Pathfinder and LISA. AIP Conference Proceedings, 873.
- A., G., & Danzmann, K. (2006). On-orbit alignment and diagnostics for the LISA Technology Package. Classical and Quantum Gravity, 23.
- C., K., & Ward, H. (2006). Construction of the LTP Optical Bench Interferometer. AIP Conference Proceedings, 873.
- G., H., & Wand, V. (2006). Interferometry for the LISA technology package LTP: an update. Journal of Physics: Conference Series, 32.
- V., W. (2006). LISA Phasemeter development. AIP Conference Proceedings, 873.
- V., W., & Ward, H. (2006). Noise sources in the LTP heterodyne interferometer. Classical and Quantum Gravity, 23.
- A., G., & Danzmann, K. (2005). Phase locking to a LISA arm: first results on a hardware model. Classical and Quantum Gravity, 22.
Proceedings Publications
- Martinez, B., Nelson, A., Hines, A., Mock, J., Sanjuan, J., Guzmán, F., & Valdés, G. (2023). Modeling, fabrication, and readout of compact optomechanical accelerometers. In Proc. SPIE 12434, MOEMS and Miniaturized Systems XXII, 1243404.More infoHigh-sensitivity accelerometers are key for many applications including ground-based gravitational wave (GW) detectors, in-situ or satellite gravimetry measurements, and inertial navigation systems. We will present our work on the development of optomechanical accelerometers based on the micro-fabrication of mechanical resonators and their integration with laser interferometers to read out their test mass dynamics under the presence of external accelerations. We will discuss the latest developments on compact millimeter-scale resonators made of fused silica and silicon, optimized for frequencies below 1 kHz and exhibiting low mechanical losses. While fused silica has demonstrated high mechanical quality factors at room temperature, silicon devices perform significantly better at very low temperatures, which is particularly relevant for future ground-based gravitational wave detectors where cryogenic environments will be used to improve the sensitivity of the observatories. We will report on our design, modeling, and fabrication process for the silicon-based resonators and present their characterization by means of highly compact fiber-based Fabry-Perot cavities.
- Wang, P., Sanjuan, J., & Guzman, F. (2023). Laser frequency stabilization using HCN gas cell. In Proc. SPIE 12665 Novel Optical Systems, Methods, and Applications.More infoLaser frequency fluctuations are one of the limiting factors for many laser-involved precision measurements such as interferometry. Laser frequency locks with the Pound-Drever-Hall (PDH) method use typically an optical cavity as a reference, which are very sensitive to environmental noises. In contrast, spectroscopy methods using atom or molecular transitions and phase modulation spectroscopy behave better in the long term. A well-sealed fiber-based Hydrogen Cyanide (HCN) gas cell that is very compact and light-weighted is chosen. And We investigate laser frequency stabilization using the absorption line of an HCN gas cell instead of a cavity to provide better frequency stability in the low-frequency regime. In our lab, a fiber-coupled HCN gas cell laser frequency lock was built and thermally stabilized to provide better long-term stability. It is designed to work with our heterodyne interferometer around 1550 nm wavelength. The HCN gas cell locking setup using phase modulation (PM) spectroscopy shows less than 0.5 MHz frequency drift over 12 hours measurement and stability levels of 1 kHz/√Hz for frequencies above 0.2 Hz.
- Nelson, A., & Guzmán, F. (2022, 2 March 2022). Compact optomechanical inertial sensors with fused silica and Si-based resonators. In Proc. SPIE 12016, Optical and Quantum Sensing and Precision Metrology II.More infoInertial sensors are used in a variety of applications including inertial navigation and precision measurements. Optical measurement of test mass displacement in a resonator allows for the creation of compact accelerometer systems. Fused silica resonators allow for excellent acceleration sensitivities due to their high mechanical quality factor, Q, at room temperature, but this changes significantly at lower temperatures. The Q factor of crystalline silicon, however, remains high at low temperatures. We work with compact fused silica resonators that operate at room temperature and aim to fabricate compact comparable mechanical resonators from Si wafers. We will report on the fabrication progress of these resonators and results from ringdown and sensitivity measurements.
- Nelson, A., Hines, A., Zhang, Y., & Guzmán, F. (2022). Optomechanical technologies for broadband inertial sensing. In Proc. SPIE 12223, Interferometry XXI.More infoAccelerometers are a vital component in inertial sensing and geodesy, gravitational physics, seismic noise detection, hydrology, and other fields requiring precision measurements. Our group develops compact low and high frequency optomechanical inertial sensors to measure acceleration for various applications. Our sensors measure the linear displacement of an oscillating test mass with displacement laser interferometers that are fiber-coupled or free space. The observed external acceleration is recovered from the displacement of the test mass. Our compact 5 Hz resonator will operate as a relative gravimeter and be read out by a compact, highly sensitive free-space heterodyne laser interferometer. It has demonstrated low mechanical losses with quality factors above 4.77 × 105 and mQ-products greater than 1200 kg. Our millimeter scale higher frequency resonators are made of fused silica for operation at room temperature and Si for operation at cryogenic temperatures. They will be readout with fiber based Fabry-Perot cavities or waveguide ring resonators that are currently under development. We are working to fabricate the Si resonators and are optimizing the process using Bosch and cryo-Si DRIE etching. Here, we report our progress on design and fabrication along with preliminary measurement results for all resonator prototypes.
- Zhang, Y., Joo, K., & Guzman, F. (2022, 5 March 2022). Fiber-based two-wavelength heterodyne displacement interferometer. In Proc. SPIE 12008, Protonic Instrumentation Engineering IX.More infoPrecision displacement laser interferometry is crucial in various applications such as microlithography, high-performance profilometry, and gravitational wave detection. We are currently developing a fiber-based heterodyne laser interferometer that features compact size and low noise floor. Laser beams at two different wavelengths are utilized to construct a fiberbased interferometer system. Narrow band spectral filters are used to separate the beams of different wavelengths and to control their optical paths. The highly common optical paths between the two interferometers provide a high commonmode rejection ratio to instrument and environmental noise sources. In this paper we present the interferometer design, benchtop prototype system, and preliminary measurement results obtained in the lab environments. A benchtop prototype shows sub-nm/Hz displacement sensitivities in air at frequencies above 100 mHz in our lab.
- Hines, A., Nelson, A., Richardson, L., Valdes, G., & Guzman, F. (2021, August 2021). Advancements in optomechanical resonators for novel inertial sensors. In Proceeding SPIE 11816 Optomechanics and Optical Alignment.More infoOur work in the Laboratory of Space Systems and Optomechanics (LASSO) at Texas A&M University involves using optomechanical resonators coupled with compact, high-precision interferometers to create novel inertial sensors. These resonators are etched from monolithic fused silica, which is known to have very low internal losses, allowing for high mechanical quality factors and low thermal acceleration noise in the test mass. Previous measurements at mTorr pressures have demonstrated Q's of 1.91 x 105, corresponding to estimated thermal acceleration noise floor on the order of 10-10 m s- 2/√Hz for frequencies above 30 mHz. In this pressure regime, gas damping is still the dominant loss mechanism. At sufficiently low pressures such that gas damping is negligible, we anticipate mechanical quality factors of the order of 106 and thermal acceleration noise at levels of 10-11 m s-2/√Hz in the sub-Hz regime. As expected, previous measurements have shown significant ambient vibrations that limit our ability to observe the noise floor of the resonator. Hence, we have developed a dedicated vibration isolation platform to mitigate external disturbances, which consists of a pendulum with a magnetic anti-spring to lower the resonant frequency. Sensors constructed with these resonators would be lightweight and cost-effective, making them promising candidates for field applications in geophysics, navigation, and site exploration.
- Wang, Y., Cervantes, F., Stambaugh, C., Smid, R., Calvo, H., Koffman, A., Pratt, J., & Lawall, J. (2014, August 2014). Alignment and testing of the NIST calculable capacitor. In Conference on Precision Electromagnetic Measurements (CPEM).More infoThis paper reports progress on the NIST effort to develop a new calculable capacitor, focusing on improvement of the guard electrode motion control as well as issues associated with the overall electrode alignment. Design of a multi-wavelength Fabry-Perot interferometer which may facilitate testing the calculable capacitor in air is also discussed.
- Killow, C., Bogenstahl, J., Perreur-Lloyd, M., Robertson, D., Steier, F., Ward, H., & Guzmán Cervantes, F. (2006). Construction of the LTP optical bench interferometer. In AIP Conference Proceedings, 873.More infoThe LISA Technology Package is an experiment that will fly onboard the LISA demonstrator mission, LISA Pathfinder. Integral to the LISA Technology Package and to LISA are ultra-stable optical benches capable of measuring inertial test mass positions to below 10pm/Hz over 1000 second timescales. Aspects of the current design and construction of the LISA Technology Package optical bench interferometer are described. © 2006 American Institute of Physics.
- Wand, V., Heinzel, G., Danzmann, K., & Guzmán, F. (2006). LISA phasemeter development. In AIP Conference Proceedings.More infoThe baseline concept of LISA had been developed within an industrial investigation by Astrium/EADS and is being reviewed since 2005 in an ongoing formulation phase. One of the most important key technology development issues remains the demonstration of the interferometric readout of the main science measurement. This includes the hardware development of an appropriate Phase Measurement System (PMS). We present the status of our work concerning the design and implementation of a LISA-like PMS with particular emphasis on the hardware development based on Field Programmable Gate Arrays (FPGA's) as main technology platform and we report on our first results demonstrating the performance of the PMS with synthetic signals. © 2006 American Institute of Physics.
Creative Productions
- Guzman, F. (2016. First direct detection of gravitational waves. Televised interview (in Spanish) to the international news channel NTN24(www.ntn24.com), Washington, DC, USA, February 11th, 2016.. International news channel NTN24. Washington DC, USA.More infoFirst direct detection of gravitational waves. Televised interview (in Spanish) to the international news channel NTN24(www.ntn24.com), Washington, DC, USA, February 11th, 2016.