Accretioninduced quasinormal mode excitation of a Schwarzschild black hole
Abstract
By combining the numerical solution of the nonlinear hydrodynamics equations with the solution of the linear inhomogeneous ZerilliMoncrief and ReggeWheeler equations, we investigate the properties of the gravitational radiation emitted during the axisymmetric accretion of matter onto a Schwarzschild black hole. The matter models considered include quadrupolar dust shells and thick accretion disks, permitting us to simulate situations which may be encountered at the end stages of stellar gravitational collapse or binary neutron star merger. We focus on the interference pattern appearing in the energy spectra of the emitted gravitational waves and on the amount of excitation of the quasinormal modes of the accreting black hole. We show that, quite generically in the presence of accretion, the blackhole ringdown is not a simple superposition of quasinormal modes, although the fundamental mode is usually present and often dominates the gravitationalwave signal. We interpret this as due to backscattering of waves off the nonexponentially decaying part of the blackhole potential and to the finite spatial extension of the accreting matter. Our results suggest that the blackhole QNM contributions to the full gravitationalwave signal should be extremely small and possibly not detectable in generic astrophysical scenarios involving the accretion of extended distributions ofmore »
 Authors:
 Dipartimento di Fisica and INFN, Politecnico di Torino, Turin (Italy)
 (Spain)
 Dipartimento di Astronomia e Scienza dello Spazio Universita di Firenze, Florence (Italy)
 Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia (Spain)
 MaxPlanckInstitut fuer Gravitationsphysik, AlbertEinsteinInstitut, PotsdamGolm (Germany)
 (Italy)
 (United States)
 Publication Date:
 OSTI Identifier:
 21011081
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.044016; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCRETION DISKS; AXIAL SYMMETRY; BACKSCATTERING; BLACK HOLES; COSMOLOGY; EMISSION; ENERGY SPECTRA; EXCITATION; GRAVITATIONAL COLLAPSE; GRAVITATIONAL RADIATION; GRAVITATIONAL WAVES; HYDRODYNAMICS; INTERFERENCE; NEUTRON STARS; NONLINEAR PROBLEMS; NUMERICAL SOLUTION; POTENTIALS
Citation Formats
Nagar, Alessandro, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Zanotti, Olindo, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Font, Jose A., Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, and Department of Physics, Louisiana State University, Baton Rouge, LA. Accretioninduced quasinormal mode excitation of a Schwarzschild black hole. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.044016.
Nagar, Alessandro, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Zanotti, Olindo, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Font, Jose A., Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, & Department of Physics, Louisiana State University, Baton Rouge, LA. Accretioninduced quasinormal mode excitation of a Schwarzschild black hole. United States. doi:10.1103/PHYSREVD.75.044016.
Nagar, Alessandro, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Zanotti, Olindo, Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia, Font, Jose A., Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, and Department of Physics, Louisiana State University, Baton Rouge, LA. Thu .
"Accretioninduced quasinormal mode excitation of a Schwarzschild black hole". United States.
doi:10.1103/PHYSREVD.75.044016.
@article{osti_21011081,
title = {Accretioninduced quasinormal mode excitation of a Schwarzschild black hole},
author = {Nagar, Alessandro and Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia and Zanotti, Olindo and Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia and Font, Jose A. and Rezzolla, Luciano and SISSA, International School for Advanced Studies and INFN, Trieste and Department of Physics, Louisiana State University, Baton Rouge, LA},
abstractNote = {By combining the numerical solution of the nonlinear hydrodynamics equations with the solution of the linear inhomogeneous ZerilliMoncrief and ReggeWheeler equations, we investigate the properties of the gravitational radiation emitted during the axisymmetric accretion of matter onto a Schwarzschild black hole. The matter models considered include quadrupolar dust shells and thick accretion disks, permitting us to simulate situations which may be encountered at the end stages of stellar gravitational collapse or binary neutron star merger. We focus on the interference pattern appearing in the energy spectra of the emitted gravitational waves and on the amount of excitation of the quasinormal modes of the accreting black hole. We show that, quite generically in the presence of accretion, the blackhole ringdown is not a simple superposition of quasinormal modes, although the fundamental mode is usually present and often dominates the gravitationalwave signal. We interpret this as due to backscattering of waves off the nonexponentially decaying part of the blackhole potential and to the finite spatial extension of the accreting matter. Our results suggest that the blackhole QNM contributions to the full gravitationalwave signal should be extremely small and possibly not detectable in generic astrophysical scenarios involving the accretion of extended distributions of matter.},
doi = {10.1103/PHYSREVD.75.044016},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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