Physical Sciences and Mathematics Commons^™

Stacked Search For Gravitational Waves From The 2006 Sgr 1900+14 Storm, 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 LIGO search for short-duration gravitational waves (GWs) associated with the 2006 March 29 SGR 1900+14 storm. A new search method is used, "stacking" the GW data around the times of individual soft-gamma bursts in the storm to enhance sensitivity for models in which multiple bursts are accompanied by GW emission. We assume that variation in the time difference between burst electromagnetic emission and potential burst GW emission is small relative to the GW signal duration, and we time-align GW excess power time-frequency tilings containing individual burst triggers to their corresponding electromagnetic emissions. We use …

Towards Improved Accuracy Of Gravitational Waves Extraction, Maria Babiuc-Hamilton

Physics Faculty Research

• 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.

All-Sky Ligo Search For Periodic Gravitational Waves In The Early Fifth-Science-Run Data, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100Hz and with the frequency's time derivative in the range -5x10^-9-0Hzs^-1. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10^-24 are obtained over a …

Lisa: Seeing The Cosmos In Low Frequency Gravitational Waves, Shane L. Larson

Colloquia and Seminars

No abstract provided.

Nonlinear Gravitational-Wave Memory From Binary Black Hole Mergers, Marc Favata

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Some astrophysical sources of gravitational waves can produce a "memory effect," which causes a permanent displacement of the test masses in a freely falling gravitational-wave detector. The Christodoulou memory is a particularly interesting nonlinear form of memory that arises from the gravitational-wave stress-energy tensor's contribution to the distant gravitational-wave field. This nonlinear memory contributes a nonoscillatory component to the gravitational-wave signal at leading (Newtonian-quadrupole) order in the waveform amplitude. Previous computations of the memory and its detectability considered only the inspiral phase of binary black hole coalescence. Using an "effective-one-body" (EOB) approach calibrated to numerical relativity simulations, as well as …

Stacked Search For Gravitational Waves From The 2006 Sgr 1900+14 Storm, B. P. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. S. Amin, S. B. Anderson, W. G. Anderson, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the results of a LIGO search for short-duration gravitational waves (GWs) associated with the 2006 March 29 SGR 1900+14 storm. A new search method is used, "stacking" the GW data around the times of individual soft-gamma bursts in the storm to enhance sensitivity for models in which multiple bursts are accompanied by GW emission. We assume that variation in the time difference between burst electromagnetic emission and potential burst GW emission is small relative to the GW signal duration, and we time-align GW excess power time-frequency tilings containing individual burst triggers to their corresponding electromagnetic emissions. We use …

Matter Sources Interacting With A Black Hole: Dynamics And Observable Signatures, Miguel Megevand

LSU Doctoral Dissertations

Dynamical systems involving black holes are one of the most promising sources of detectable gravitational waves. Additionally, one expects strong electromagnetic signals whenever matter sources are present. In this dissertation, we study different astrophysical scenarios pertaining the interaction of matter with a black hole. We first investigate the possibility to localize scalar field configurations surrounding a (dynamic) black hole. The analytical study is illustrated by performing numerical simulations that show the evolution of a Klein-Gordon-like scalar field shell surrounding a black hole. Second, we present a method to estimate the gravitational wave frequency at the end of the inspiral phase …