Gravitational waves from oscillating accretion tori: Comparison between different approaches

Journal Article · Fri Jul 15 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.024007· OSTI ID:20711129

Nagar, Alessandro ^[1]; Font, Jose A; Zanotti, Olindo ^[1]; Pietri, Roberto De ^[2]

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1. Departament d'Astronomia i Astrofisica, Universitat de Valencia, Edifici d'Investigacio, Dr. Moliner 50, 46100 Burjassot (Valencia) (Spain)
2. Dipartimento di Fisica, Universita di Parma, Parco Area delle Scienze 7a, 43100, Parma (Italy)

Quasiperiodic oscillations of high density thick accretion disks orbiting a Schwarzschild black hole have been recently addressed as interesting sources of gravitational waves. The aim of this paper is to compare the gravitational waveforms emitted from these sources when computed using (variations of) the standard quadrupole formula and gauge-invariant metric perturbation theory. To this goal we evolve representative disk models using an existing general relativistic hydrodynamics code which has been previously employed in investigations of such astrophysical systems. Two are the main results of this work: First, for stable and marginally stable disks, no excitation of the black hole quasinormal modes is found. Second, we provide a simple, relativistic modification of the Newtonian quadrupole formula which, in certain regimes, yields excellent agreement with the perturbative approach. This holds true as long as back-scattering of GWs is negligible. Otherwise, any functional form of the quadrupole formula yields systematic errors {approx}10%.

• OSTI ID: 20711129
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 2 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCRETION DISKS
BACKSCATTERING
BLACK HOLES
COMPARATIVE EVALUATIONS
COSMOLOGY
EMISSION
EXCITATION
GAUGE INVARIANCE
GRAVITATIONAL WAVES
HYDRODYNAMICS
PERTURBATION THEORY
QUADRUPOLES
RELATIVISTIC RANGE
SCHWARZSCHILD METRIC
WAVE FORMS