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Articles 1  30 of 79
FullText Articles in Physics
The Delay Time Of Gravitational Wave — GammaRay Burst Associations, Bing Zhang
The Delay Time Of Gravitational Wave — GammaRay Burst Associations, Bing Zhang
Physics & Astronomy Faculty Publications
The first gravitational wave (GW) — gammaray burst (GRB) association, GW170817/GRB 170817A, had an offset in time, with the GRB trigger time delayed by ∼1.7 s with respect to the merger time of the GW signal. We generally discuss the astrophysical origin of the delay time, Δt, of GWGRB associations within the context of compact binary coalescence (CBC) — short GRB (sGRB) associations and GW burst — long GRB (lGRB) associations. In general, the delay time should include three terms, the time to launch a clean (relativistic) jet, Δtjet; the time for the jet to break out from the surrounding medium ...
LowLatency GravitationalWave Alerts For Multimessenger Astronomy During The Second Advanced Ligo And Virgo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
LowLatency GravitationalWave Alerts For Multimessenger Astronomy During The Second Advanced Ligo And Virgo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
Advanced LIGO's second observing run (O2), conducted from 2016 November 30 to 2017 August 25, combined with Advanced Virgo's first observations in 2017 August, witnessed the birth of gravitationalwave multimessenger astronomy. The first ever gravitationalwave detection from the coalescence of two neutron stars, GW170817, and its gammaray counterpart, GRB 170817A, led to an electromagnetic followup of the event at an unprecedented scale. Several teams from across the world searched for EM/neutrino counterparts to GW170817, paving the way for the discovery of optical, Xray, and radio counterparts. In this article, we describe the online identification of gravitationalwave transients ...
Search For Multimessenger Sources Of Gravitational Waves And HighEnergy Neutrinos With Advanced Ligo During Its First Observing Run, Antares, And Icecube, A. Albert, M. André, M. Anghinolfi, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Search For Multimessenger Sources Of Gravitational Waves And HighEnergy Neutrinos With Advanced Ligo During Its First Observing Run, Antares, And Icecube, A. Albert, M. André, M. Anghinolfi, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
Astrophysical sources of gravitational waves, such as binary neutron star and black hole mergers or corecollapse supernovae, can drive relativistic outflows, giving rise to nonthermal highenergy emission. Highenergy neutrinos are signatures of such outflows. The detection of gravitational waves and highenergy neutrinos from common sources could help establish the connection between the dynamics of the progenitor and the properties of the outflow. We searched for associated emission of gravitational waves and highenergy neutrinos from astrophysical transients with minimal assumptions using data from Advanced LIGO from its first observing run O1, and data from the Antares and IceCube neutrino observatories from ...
A Fermi GammaRay Burst Monitor Search For Electromagnetic Signals Coincident With GravitationalWave Candidates In Advanced Ligo's First Observing Run, E. Burns, A. Goldstein, C. M. Hui, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
A Fermi GammaRay Burst Monitor Search For Electromagnetic Signals Coincident With GravitationalWave Candidates In Advanced Ligo's First Observing Run, E. Burns, A. Goldstein, C. M. Hui, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present a search for prompt gammaray counterparts to compact binary coalescence gravitational wave (GW) candidates from Advanced LIGO's first observing run (O1). As demonstrated by the multimessenger observations of GW170817/GRB 170817A, electromagnetic and GW observations provide complementary information about the astrophysical source, and in the case of weaker candidates, may strengthen the case for an astrophysical origin. Here we investigate lowsignificance GW candidates from the O1 compact binary coalescence searches using the Fermi GammaRay Burst Monitor (GBM), leveraging its all sky and broad energy coverage. Candidates are ranked and compared to background to measure the significance. Those ...
Prospects For Observing And Localizing GravitationalWave Transients With Advanced Ligo, Advanced Virgo And Kagra, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Prospects For Observing And Localizing GravitationalWave Transients With Advanced Ligo, Advanced Virgo And Kagra, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitationalwave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multimessenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitationalwave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitationalwave transients, with particular focus on gravitationalwave signals from the inspiral of binary neutron star systems, which are the most promising targets for multimessenger astronomy. The ability to localize the sources ...
Broadband Measurement And Reduction Of Quantum Radiation Pressure Noise In The Audio Band, Jonathan Daniel Cripe
Broadband Measurement And Reduction Of Quantum Radiation Pressure Noise In The Audio Band, Jonathan Daniel Cripe
LSU Doctoral Dissertations
One hundred years after Albert Einstein predicted the existence of gravitational waves in his general theory of relativity, the Laser Interferometer GravitationalWave Observatory (LIGO) made the first direct detection of gravitational waves. Since the first detection of gravitational waves from a binary black hole merger, LIGO has gone on to detect gravitational waves from multiple binary black hole mergers, and more recently from a binary neutron star merger in collaboration with telescopes around the world. The detection of gravitational waves has opened a new window to the universe and has launched the era of gravitational wave astronomy.
With the first ...
Search For Compact Object Coalescences And Understanding Their Significance Using Data From Advanced Ligo, Debnandini Mukherjee
Search For Compact Object Coalescences And Understanding Their Significance Using Data From Advanced Ligo, Debnandini Mukherjee
Theses and Dissertations
Gravitational waves were observed for the first time on September 14, 2015. A 36 and a 29 solar mass black holes were seen to inspiral around each other and merge about 410 Mpc away. This gave momentum to the areas of gravitational wave astrophysics and astronomy. While the universe could be perceived in the electromagnetic spectrum so far, enabling us to "see" it with telescopes, it could now be "listened to" using gravitational waves. Also, black holes being optically dark, could be observed directly for the very first time after this discovery. The 100 year old theory of General Relativity ...
Undergraduate Research In Gravitational Waves Astronomy At Marshall University, Maria BabiucHamilton
Undergraduate Research In Gravitational Waves Astronomy At Marshall University, Maria BabiucHamilton
Maria C. BabiucHamilton
This is a presentation of undergraduate student research into gravitational waves at Marshall University.
Gw170608: Observation Of A 19 SolarMass Binary Black Hole Coalescence, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Gw170608: Observation Of A 19 SolarMass Binary Black Hole Coalescence, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
On 2017 June 8 at 02:01:16.49 UTC, a gravitationalwave (GW) signal from the merger of two stellarmass blackholes was observed by the two Advanced Laser Interferometer GravitationalWave Observatory detectors with a network signaltonoise ratio of 13. This system is the lightest black hole binary so far observed, with component masses of 12^{+7}_{ 2}M⊙^{+2}_{2}M⊙ (90% credible intervals). These lie in the range of measured black hole masses in lowmass Xray binaries, thus allowing us to compare black holes detected through GWs with electromagnetic observations. The source's luminosity distance is 340^{+140} _{140 ...}
Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
The source of the gravitationalwave (GW) signal GW170817, very likely a binary neutron star merger, was also observed electromagnetically, providing the first multimessenger observations of this type. The twoweeklong electromagnetic (EM) counterpart had a signature indicative of an rprocessinduced 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 ...
On The Progenitor Of Binary Neutron Star Merger Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
On The Progenitor Of Binary Neutron Star Merger Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
On 2017 August 17 the merger of two compact objects with masses consistent with two neutron stars was discovered through gravitationalwave (GW170817), gammaray (GRB 170817A), and optical (SSS17a/AT 2017gfo) observations. The optical source was associated with the earlytype galaxy NGC 4993 at a distance of just ∼40 Mpc, consistent with the gravitationalwave 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 ...
Search For HighEnergy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, Antares Collaboration, The Icecube Collaboration, The Pierre Auger Collaboration, Ligo Scientific Collaboration, Virgo Collaboration, Karen Andeen
Search For HighEnergy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, Antares Collaboration, The Icecube Collaboration, The Pierre Auger Collaboration, Ligo Scientific Collaboration, Virgo Collaboration, Karen Andeen
Physics Faculty Research and Publications
The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gammaray burst (GRB) that followed the merger of this binary was also recorded by the FermiGammaray Burst Monitor (FermiGBM), and the AntiCoincidence Shield for the Spectrometer for the International GammaRay 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 highenergy neutrinos from the merger in the GeV–EeV energy range using the Antares, IceCube, and Pierre Auger Observatories. No neutrinos ...
Search For HighEnergy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, A. Albert, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Search For HighEnergy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, A. Albert, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gammaray burst (GRB) that followed the merger of this binary was also recorded by the Fermi Gammaray Burst Monitor (FermiGBM), and the AntiCoincidence Shield for the Spectrometer for the International GammaRay 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 highenergy neutrinos from the merger in the GeVEeV energy range using the Antares, IceCube, and Pierre Auger Observatories. No neutrinos directionally ...
MultiMessenger Observations Of A Binary Neutron Star Merger, Karen Andeen
MultiMessenger Observations Of A Binary Neutron Star Merger, Karen Andeen
Physics Faculty Research and Publications
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gammaray Burst Monitor independently detected a gammaray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitationalwave signal, the source was initially localized to a sky region of 31 deg^{2} at a luminosity distance of Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the ...
MultiMessenger Observations Of A Binary Neutron Star Merger, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
MultiMessenger Observations Of A Binary Neutron Star Merger, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gammaray Burst Monitor independently detected a gammaray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitationalwave signal, the source was initially localized to a sky region of 31 deg^{2} at a luminosity distance of 40^{+ 8}_{8} Mpc and with component masses consistent with neutron stars. The component masses were later measured to ...
Upper Limits On Gravitational Waves From Scorpius X1 From A ModelBased CrossCorrelation Search In Advanced Ligo Data, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Upper Limits On Gravitational Waves From Scorpius X1 From A ModelBased CrossCorrelation Search In Advanced Ligo Data, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the results of a semicoherent search for continuous gravitational waves from the lowmass Xray binary Scorpius X1, 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 252000 Hz, spanning the current observationally constrained range of binary orbital parameters. No significant detection candidates were found, and frequencydependent upper limits were set using a combination of sensitivity estimates ...
Towards A Standardized Characteristic Extraction Tool, Maria BabiucHamilton
Towards A Standardized Characteristic Extraction Tool, Maria BabiucHamilton
Maria C. BabiucHamilton
Knowing the precise details of the gravitational wave signature obtained from numerical simulations of binary black hole mergers is a key requirement for meaningful detection and scientific interpretation of the data. However, the waveforms are not easy to be accurately computed. The importance of this problem to the future of gravitational wave astronomy is well recognized. CauchyCharacteristic Extraction (CCE) is the most precise and refined extraction method available. The CCE technique connects the strongfield Cauchy evolution of the spacetime near the merger to the characteristic evolution to future null infinity where the waveform is extracted in an unambiguous way. Recently ...
Simulating Magnetospheres With Numerical Relativity: The Giraffe Code, Maria BabiucHamilton
Simulating Magnetospheres With Numerical Relativity: The Giraffe Code, Maria BabiucHamilton
Maria C. BabiucHamilton
Numerical Relativity is successful in the simulation of black holes and gravitational waves. In recent years, teams have tackled the problem of the interaction of gravitational and electromagnetic waves. We developed a new code for the numerical simulation of neutron and black hole magnetospheres, using the FFE formalism. We tested the performance of the new code named GiRaFFE, in 1D and 3D test suits. We will study magnetospheres, focusing on jets by the Blandford Znajek mechanism.
Towards A Fully Nonlinear Cauchy Characteristic Extraction, Maria BabiucHamilton
Towards A Fully Nonlinear Cauchy Characteristic Extraction, Maria BabiucHamilton
Maria C. BabiucHamilton
The artificial finite outer boundary present in Cauchy codes introduce two sources of error: The outer boundary condition and waveform extraction at an inner worldtube. The problem of proper boundary condition for a radiating system can be solved only by extension to Ι+ (conformal compactification). Cauchy Characteristic Extraction (CCE) offers a means to avoid these errors.
Towards Improved Accuracy Of Gravitational Waves Extraction, Maria BabiucHamilton
Towards Improved Accuracy Of Gravitational Waves Extraction, Maria BabiucHamilton
Maria C. BabiucHamilton
Results in developing two new methods to improve the accuracy of waveform extraction using characteristic evolution. Numerical method: circular boundaries, with angular dissipation in the characteristic code. Geometric method: computation of Weyl tensor component Y4 at null infinity, in a conformally compactified treatment. Comparison and calibration in tests problems based upon linearized waves.
Gravitational & Electromagnetic Waves On The Null Cone, Maria BabiucHamilton
Gravitational & Electromagnetic Waves On The Null Cone, Maria BabiucHamilton
Maria C. BabiucHamilton
Bondi (1962) proved mathematically the existence of gravitational waves at null infinity. He found an exact solution of Einstein equations. Within this metric, he calculated the loss of mass due to the emission of gravitational waves. The mas of a system is constant if and only if there is no news. If there is news, the mass decreases as long as there are news.
Steps Towards A Nonlinear CauchyCharacteristic Code Patching, Maria BabiucHamilton
Steps Towards A Nonlinear CauchyCharacteristic Code Patching, Maria BabiucHamilton
Maria C. BabiucHamilton
Cauchycharacteristic extractions (CCE) avoids the errors due to extraction at finite worldtube. The Cauchy and the characteristic approaches have complementary strengths and weaknesses. Unification of the two methods is a promising way of combining the strengths of both formalisms.
An Analysis Of The Gravitational Waves Null Memory, Maria BabiucHamilton
An Analysis Of The Gravitational Waves Null Memory, Maria BabiucHamilton
Maria C. BabiucHamilton
Gravitational wave astronomy sees (hears) gravitational waves by observing the phenomena of gravitational and electromagnetic memory, and the formation of trapped surfaces and horizons.
Tools For Gravitational Wave Astronomy, Maria BabiucHamilton
Tools For Gravitational Wave Astronomy, Maria BabiucHamilton
Maria C. BabiucHamilton
Gravitational waves have been confirmed. Tools are available for their study, including the Einstein Toolkit, SimulationTools and the SXS Gravitational Waveform Database.
A New Algorithm For The Numerical Computation Of Gravitational Waves, Maria BabiucHamilton, Jeff Winicour
A New Algorithm For The Numerical Computation Of Gravitational Waves, Maria BabiucHamilton, Jeff Winicour
Maria C. BabiucHamilton
With gravitational waves, Gravitational Wave Astronomy can “see” colliding back holes and galaxies, the birth of a black hole in a supernova, the growth pains of our universe and the structure of spacetime.
Gravitational Wave Behavior At A VacuumMatter Interface, Jake Litterer
Gravitational Wave Behavior At A VacuumMatter Interface, Jake Litterer
Honors Program Theses
In classical electrodynamics, boundary conditions of the E and B fields are derived from Maxwell's equations, which are used to derive the Fresnel equations describing the behavior of a wave at an interface between media with given indices of refraction. Though electrodynamics and gravity are in some instances strikingly analogous, boundary conditions in general relativity are somewhat more opaque. We will see that while while continuity of the metric must be true in general, discontinuity of the extrinsic curvature of spacetime, while allowed by the Einstein field equations, results in a singularity in the energymomentum tensor. This singularity is ...
Search For Gravitational Waves Associated With GammaRay Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Search For Gravitational Waves Associated With GammaRay Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the results of the search for gravitational waves (GWs) associated with γray bursts detected during the first observing run of the Advanced Laser Interferometer GravitationalWave Observatory (LIGO). We find no evidence of a GW signal for any of the 41 γray bursts for which LIGO data are available with sufficient duration. For all γray bursts, we place lower bounds on the distance to the source using the optimistic assumption that GWs with an energy of were emitted within theHz band, and we find a median 90% confidence limit of 71 Mpc at 150 Hz. For the subset of ...
First Search For Gravitational Waves From Known Pulsars With Advanced Ligo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
First Search For Gravitational Waves From Known Pulsars With Advanced Ligo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present the result of searches for gravitational waves from 200 pulsars using data from the first observing run of the Advanced LIGO detectors. We find no significant evidence for a gravitationalwave signal from any of these pulsars, but we are able to set the most constraining upper limits yet on their gravitationalwave amplitudes and ellipticities. For eight of these pulsars, our upper limits give bounds that are improvements over the indirect spindown limit values. For another 32, we are within a factor of 10 of the spindown limit, and it is likely that some of these will be reachable ...
Prospects For Observing And Localizing GravitationalWave Transients With Advanced Ligo And Advanced Virgo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Prospects For Observing And Localizing GravitationalWave Transients With Advanced Ligo And Advanced Virgo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
We present a possible observing scenario for the Advanced LIGO and Advanced Virgo gravitationalwave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multimessenger astronomy with gravitational waves. We determine the expected sensitivity of the network to transient gravitationalwave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitationalwave transients, with particular focus on gravitationalwave signals from the inspiral of binary neutronstar systems, which are considered the most promising for multimessenger astronomy. The ability to localize the sources ...
The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.
Physics Faculty Research & Creative Works
A transient gravitationalwave signal, GW150914, was identified in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To assess the implications of this discovery, the detectors remained in operation with unchanged configurations over a period of 39 days around the time of the signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous twodetector observational data is estimated to have a falsealarm rate (FAR) of < 4.9 x 10^{6} yr^{1}, yielding a pvalue for GW150914 of < 2 x 10^{7}. Parameter estimation followup on this trigger identifies its source ...