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Fluids In Music: The Mathematics Of Pan’S Flutes, Bogdan Nita, Sajan Ramanathan Oct 2019

Fluids In Music: The Mathematics Of Pan’S Flutes, Bogdan Nita, Sajan Ramanathan

Department of Mathematics Facuty Scholarship and Creative Works

We discuss the mathematics behind the Pan’s flute. We analyze how the sound is created, the relationship between the notes that the pipes produce, their frequencies and the length of the pipes. We find an equation which models the curve that appears at the bottom of any Pan’s flute due to the different pipe lengths.


Properties Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Jan 2019

Properties Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On August 17, 2017, the Advanced LIGO and Advanced Virgo gravitational-wave detectors observed a low-mass compact binary inspiral. The initial sky localization of the source of the gravitational-wave signal, GW170817, allowed electromagnetic observatories to identify NGC 4993 as the host galaxy. In this work, we improve initial estimates of the binary's properties, including component masses, spins, and tidal parameters, using the known source location, improved modeling, and recalibrated Virgo data. We extend the range of gravitational-wave frequencies considered down to 23 Hz, compared to 30 Hz in the initial analysis. We also compare results inferred using several signal models, which …


Search For Sub-Solar Mass Ultracompact Binaries In Advanced Ligo's First Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2018

Search For Sub-Solar Mass Ultracompact Binaries In Advanced Ligo's First Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2 M-1.0 M using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2 M, 0.2 M) ultracompact binaries to be less than 1.0×106 Gpc-3 yr-1 and the coalescence rate of a similar distribution of (1.0 M, 1.0 M) ultracompact binaries to be less than 1.9×104 Gpc-3 yr-1 (at 90% confidence). Neither black holes nor neutron stars are expected to …


Prospects For Observing And Localizing Gravitational-Wave Transients With Advanced Ligo, Advanced Virgo And Kagra, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2018

Prospects For Observing And Localizing Gravitational-Wave Transients With Advanced Ligo, Advanced Virgo And Kagra, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources …


Gw170817: Measurements Of Neutron Star Radii And Equation Of State, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Oct 2018

Gw170817: Measurements Of Neutron Star Radii And Equation Of State, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were …


Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin May 2018

Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find …


Constraints On Cosmic Strings Using Data From The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, Marc Favata, Shaon Ghosh May 2018

Constraints On Cosmic Strings Using Data From The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such …


Full Band All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin May 2018

Full Band All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We report on a new all-sky search for periodic gravitational waves in the frequency band 475-2000 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Potential signals could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the data from Advanced LIGO's first observational run O1. No gravitational-wave signals were observed, and upper limits were placed on their strengths. For completeness, results from the separately published low-frequency search 20-475 Hz are included as well. Our lowest upper limit on worst-case (linearly polarized) strain amplitude h0 is ∼4×10-25 …


Gw170817: Implications For The Stochastic Gravitational-Wave Background From Compact Binary Coalescences, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Feb 2018

Gw170817: Implications For The Stochastic Gravitational-Wave Background From Compact Binary Coalescences, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The LIGO Scientific and Virgo Collaborations have announced the event GW170817, the first detection of gravitational waves from the coalescence of two neutron stars. The merger rate of binary neutron stars estimated from this event suggests that distant, unresolvable binary neutron stars create a significant astrophysical stochastic gravitational-wave background. The binary neutron star component will add to the contribution from binary black holes, increasing the amplitude of the total astrophysical background relative to previous expectations. In the Advanced LIGO-Virgo frequency band most sensitive to stochastic backgrounds (near 25 Hz), we predict a total astrophysical background with amplitude ΩGW(f=25 Hz)=1.8-1.3+2.7×10-9 with …


All-Sky Search For Long-Duration Gravitational Wave Transients In The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh Feb 2018

All-Sky Search For Long-Duration Gravitational Wave Transients In The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the results of a search for long-duration gravitational wave transients in the data of the LIGO Hanford and LIGO Livingston second generation detectors between September 2015 and January 2016, with a total observational time of 49 d. The search targets gravitational wave transients of 10500 s duration in a frequency band of 242048 Hz, with minimal assumptions about the signal waveform, polarization, source direction, time of occurrence. No significant events were observed. As a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. We also …


Effects Of Data Quality Vetoes On A Search For Compact Binary Coalescences In Advanced Ligo's First Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh Feb 2018

Effects Of Data Quality Vetoes On A Search For Compact Binary Coalescences In Advanced Ligo's First Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The first observing run of Advanced LIGO spanned 4 months, from 12 September 2015 to 19 January 2016, during which gravitational waves were directly detected from two binary black hole systems, namely GW150914 and GW151226. Confident detection of gravitational waves requires an understanding of instrumental transients and artifacts that can reduce the sensitivity of a search. Studies of the quality of the detector data yield insights into the cause of instrumental artifacts and data quality vetoes specific to a search are produced to mitigate the effects of problematic data. In this paper, the systematic removal of noisy data from analysis …


First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Marc Favata, Shaon Ghosh Jan 2018

First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present results from the first directed search for nontensorial gravitational waves. While general relativity allows for tensorial (plus and cross) modes only, a generic metric theory may, in principle, predict waves with up to six different polarizations. This analysis is sensitive to continuous signals of scalar, vector, or tensor polarizations, and does not rely on any specific theory of gravity. After searching data from the first observation run of the advanced LIGO detectors for signals at twice the rotational frequency of 200 known pulsars, we find no evidence of gravitational waves of any polarization. We report the first upper …


Gw170608: Observation Of A 19 Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

Gw170608: Observation Of A 19 Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On 2017 June 8 at 02:01:16.49 UTC, a gravitational-wave (GW) signal from the merger of two stellar-mass blackholes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with anetwork signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with componentmasses of 12+7-2M⊙7+2-2 (90% credible intervals). These lie in the range of measured black hole masses inlow-mass X-ray binaries, thus allowing us to compare black holes detected through GWs with electromagneticobservations. The source's luminosity distance is 340+140-140corresponding to redshift -0.07+0.03003. We verify thatthe signal waveform is consistent with the predictions of general relativity.


First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, M. C. Araya, Marc Favata, Shaon Ghosh Dec 2017

First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, M. C. Araya, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100 Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7 …


First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars …


Search For Post-Merger Gravitational Waves From The Remnant Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

Search For Post-Merger Gravitational Waves From The Remnant Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The first observation of a binary neutron star (NS) coalescence by the Advanced LIGO and Advanced Virgo gravitational-wave (GW) detectors offers an unprecedented opportunity to study matter under the most extreme conditions. After such a merger, a compact remnant is left over whose nature depends primarily on the masses of the inspiraling objects and on the equation of state of nuclear matter. This could be either a black hole (BH) or an NS, with the latter being either long-lived or too massive for stability implying delayed collapse to a BH. Here, we present a search for GWs from the remnant …


Flow Anisotropy Due To Thread-Like Nanoparticle Agglomerations In Dilute Ferrofluids, Alexander Cali, Wah-Keat Lee, A. David Trubatch, Philip Yecko Dec 2017

Flow Anisotropy Due To Thread-Like Nanoparticle Agglomerations In Dilute Ferrofluids, Alexander Cali, Wah-Keat Lee, A. David Trubatch, Philip Yecko

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

Improved knowledge of the magnetic field dependent flow properties of nanoparticle-based magnetic fluids is critical to the design of biomedical applications, including drug delivery and cell sorting. To probe the rheology of ferrofluid on a sub-millimeter scale, we examine the paths of 550 μm diameter glass spheres falling due to gravity in dilute ferrofluid, imposing a uniform magnetic field at an angle with respect to the vertical. Visualization of the spheres’ trajectories is achieved using high resolution X-ray phase-contrast imaging, allowing measurement of a terminal velocity while simultaneously revealing the formation of an array of long thread-like accumulations of magnetic …


Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The source of the gravitational-wave (GW) signal GW170817, very likely a binary neutron star merger, was also observed electromagnetically, providing the first multi-messenger observations of this type. The two-week-long electromagnetic (EM) counterpart had a signature indicative of an r-process-induced optical transient known as a kilonova. This Letter examines how the mass of the dynamical ejecta can be estimated without a direct electromagnetic observation of the kilonova, using GW measurements and a phenomenological model calibrated to numerical simulations of mergers with dynamical ejecta. Specifically, we apply the model to the binary masses inferred from the GW measurements, and use the resulting …


On The Progenitor Of Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

On The Progenitor Of Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On 2017 August 17 the merger of two compact objects with masses consistent with two neutron stars was discovered through gravitational-wave (GW170817), gamma-ray (GRB 170817A), and optical (SSS17a/AT 2017gfo) observations. The optical source was associated with the early-type galaxy NGC 4993 at a distance of just ∼40 Mpc, consistent with the gravitational-wave measurement, and the merger was localized to be at a projected distance of ∼2 kpc away from the galaxy's center. We use this minimal set of facts and the mass posteriors of the two neutron stars to derive the first constraints on the progenitor of GW170817 at the …


Search For High-Energy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, A. Albert, M. André, M. Anghinolfi, M. Ardid, J. J. Aubert, J. Aublin, T. Avgitas, Marc Favata, Shaon Ghosh, Rodica Martin Dec 2017

Search For High-Energy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, A. Albert, M. André, M. Anghinolfi, M. Ardid, J. J. Aubert, J. Aublin, T. Avgitas, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merger of this binary was also recorded by the Fermi Gamma-ray Burst Monitor (Fermi-GBM), and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory (INTEGRAL), indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the GeV-EeV energy range using the Antares, IceCube, and Pierre Auger Observatories. No neutrinos directionally coincident …


Gravitational Waves And Gamma-Rays From A Binary Neutron Star Merger: Gw170817 And Grb 170817a, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Oct 2017

Gravitational Waves And Gamma-Rays From A Binary Neutron Star Merger: Gw170817 And Grb 170817a, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On 2017 August 17, the gravitational-wave event GW170817 was observed by the Advanced LIGO and Virgo detectors, and the gamma-ray burst (GRB) GRB 170817A was observed independently by the Fermi Gamma-ray Burst Monitor, and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory. The probability of the near-simultaneous temporal and spatial observation of GRB 170817A and GW170817 occurring by chance is 5.0 × 10-8. We therefore confirm binary neutron star mergers as a progenitor of short GRBs. The association of GW170817 and GRB 170817A provides new insight into fundamental physics and the origin of short GRBs. We …


Gw170817: Observation Of Gravitational Waves From A Binary Neutron Star Inspiral, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Oct 2017

Gw170817: Observation Of Gravitational Waves From A Binary Neutron Star Inspiral, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On August 17, 2017 at 12-41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per 8.0×104 years. We infer the component masses of the binary to be between 0.86 and 2.26 M, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range 1.17-1.60 M, with the total mass of …


Gw170814: A Three-Detector Observation Of Gravitational Waves From A Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin Oct 2017

Gw170814: A Three-Detector Observation Of Gravitational Waves From A Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

On August 14, 2017 at 10 30:43 UTC, the Advanced Virgo detector and the two Advanced LIGO detectors coherently observed a transient gravitational-wave signal produced by the coalescence of two stellar mass black holes, with a false-alarm rate of 1 in 27 000 years. The signal was observed with a three-detector network matched-filter signal-to-noise ratio of 18. The inferred masses of the initial black holes are 30.5-3.0+5.7M and 25.3-4.2+2.8M (at the 90% credible level). The luminosity distance of the source is 540-210+130 Mpc, corresponding to a redshift of z=0.11-0.04+0.03. A network of three detectors improves the sky localization of the …


Upper Limits On Gravitational Waves From Scorpius X-1 From A Model-Based Cross-Correlation Search In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh Sep 2017

Upper Limits On Gravitational Waves From Scorpius X-1 From A Model-Based Cross-Correlation Search In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the results of a semicoherent search for continuous gravitational waves from the low-mass X-ray binary Scorpius X-1, using data from the first Advanced LIGO observing run. The search method uses details of the modeled, parametrized continuous signal to combine coherently data separated by less than a specified coherence time, which can be adjusted to trade off sensitivity against computational cost. A search was conducted over the frequency range 25-2000 Hz, spanning the current observationally constrained range of binary orbital parameters. No significant detection candidates were found, and frequency-dependent upper limits were set using a combination of sensitivity estimates …


All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, Marc Favata, Shaon Ghosh Sep 2017

All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We report on an all-sky search for periodic gravitational waves in the frequency band 20-475 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Such a signal could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our galaxy. This search uses the data from Advanced LIGO's first observational run, O1. No periodic gravitational wave signals were observed, and upper limits were placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼4×10-25 near 170 Hz. For a circularly polarized source (most favorable orientation), the smallest …


Search For Intermediate Mass Black Hole Binaries In The First Observing Run Of Advanced Ligo, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, H. Almoubayyed, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, Marc Favata, Shaon Ghosh Jul 2017

Search For Intermediate Mass Black Hole Binaries In The First Observing Run Of Advanced Ligo, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, H. Almoubayyed, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

During their first observational run, the two Advanced LIGO detectors attained an unprecedented sensitivity, resulting in the first direct detections of gravitational-wave signals produced by stellar-mass binary black hole systems. This paper reports on an all-sky search for gravitational waves (GWs) from merging intermediate mass black hole binaries (IMBHBs). The combined results from two independent search techniques were used in this study: the first employs a matched-filter algorithm that uses a bank of filters covering the GW signal parameter space, while the second is a generic search for GW transients (bursts). No GWs from IMBHBs were detected; therefore, we constrain …


Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, H. Almoubayyed, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh Jun 2017

Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, H. Almoubayyed, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Results are presented from a semicoherent search for continuous gravitational waves from the brightest low-mass X-ray binary, Scorpius X-1, using data collected during the first Advanced LIGO observing run. The search combines a frequency domain matched filter (Bessel-weighted F-statistic) with a hidden Markov model to track wandering of the neutron star spin frequency. No evidence of gravitational waves is found in the frequency range 60-650 Hz. Frequentist 95% confidence strain upper limits, h095%=4.0×10-25, 8.3×10-25, and 3.0×10-25 for electromagnetically restricted source orientation, unknown polarization, and circular polarization, respectively, are reported at 106 Hz. They are ≤10 times higher than the theoretical …


Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh Jun 2017

Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10 11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2-6.0+8.4M' and 19.4-5.9+5.3M (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, a mass-weighted combination …


Search For Gravitational Waves Associated With Gamma-Ray Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh Jun 2017

Search For Gravitational Waves Associated With Gamma-Ray Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the results of the search for gravitational waves (GWs) associated with γ-ray bursts detected during the first observing run of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO). We find no evidence of a GW signal for any of the 41 γ-ray bursts for which LIGO data are available with sufficient duration. For all γ-ray bursts, we place lower bounds on the distance to the source using the optimistic assumption that GWs with an energy of were emitted within the-Hz band, and we find a median 90% confidence limit of 71 Mpc at 150 Hz. For the subset of …


Search For Continuous Gravitational Waves From Neutron Stars In Globular Cluster Ngc 6544, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh Apr 2017

Search For Continuous Gravitational Waves From Neutron Stars In Globular Cluster Ngc 6544, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, Marc Favata, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We describe a directed search for continuous gravitational waves in data from the sixth initial LIGO science run. The target was the nearby globular cluster NGC 6544 at a distance of ≈2.7 kpc. The search covered a broad band of frequencies along with first and second frequency derivatives for a fixed sky position. The search coherently integrated data from the two LIGO interferometers over a time span of 9.2 days using the matched-filtering F-statistic. We found no gravitational-wave signals and set 95% confidence upper limits as stringent as 6.0×10-25 on intrinsic strain and 8.5×10-6 on fiducial ellipticity. These values beat …