Quasi-periodic accretion and gravitational waves from oscillating 'toroidal neutron stars' around a Schwarzschild black hole

被引:94
作者
Zanotti, O
Rezzolla, L
Font, JA
机构
[1] SISSA, Int Sch Adv Studies, I-34014 Trieste, Italy
[2] Ist Nazl Fis Nucl, Sez Trieste, I-34127 Trieste, Italy
[3] Univ Valencia, Dept Astron & Astrofis, Valencia 46100, Spain
关键词
accretion; accretion discs; gravitational waves; hydrodynamics; relativity; stars : oscillations;
D O I
10.1046/j.1365-8711.2003.06474.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present general relativistic hydrodynamics simulations of constant specific angular momentum tori orbiting a Schwarzschild black hole. These tori are expected to form as a result of stellar gravitational collapse, binary neutron star merger or disruption, can reach very high rest-mass densities and behave effectively as neutron stars but with a toroidal topology (i.e. 'toroidal neutron stars'). Here our attention is focused on the dynamical response of these objects to axisymmetric perturbations. We show that upon the introduction of perturbations, these systems either become unstable to the runaway instability or exhibit a regular oscillatory behaviour, resulting in a quasi-periodic variation of the accretion rate as well as of the mass quadrupole. The latter, in particular, is responsible for the emission of intense gravitational radiation for which the signal-to-noise ratio at the detector is comparable to or larger than the typical one expected in stellar-core collapse, making these new sources of gravitational waves potentially detectable. We discuss a systematic investigation of the parameter space in both the linear and non-linear regimes, providing estimates of how the gravitational radiation emitted depends on the mass of the torus and on the strength of the perturbation.
引用
收藏
页码:832 / 848
页数:17
相关论文
共 57 条
[1]  
ABRAMOWICZ M, 1978, ASTRON ASTROPHYS, V63, P221
[2]  
Abramowicz M. A., 1974, Acta Astronomica, V24, P45
[3]  
Abramowicz MA, 1998, ASTRON ASTROPHYS, V331, P1143
[4]   RUNAWAY INSTABILITY IN ACCRETION DISKS ORBITING BLACK-HOLES [J].
ABRAMOWICZ, MA ;
CALVANI, M ;
NOBILI, L .
NATURE, 1983, 302 (5909) :597-599
[5]  
[Anonymous], 1987, 300 YEARS GRAVITATIO
[6]   Uniformly rotating axisymmetric fluid configurations bifurcating from highly flattened Maclaurin spheroids [J].
Ansorg, M ;
Kleinwächter, A ;
Meinel, R .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 339 (02) :515-523
[7]   Numerical {3+1} general relativistic hydrodynamics: A local characteristic approach [J].
Banyuls, F ;
Font, JA ;
Ibanez, JM ;
Marti, JM ;
Miralles, JA .
ASTROPHYSICAL JOURNAL, 1997, 476 (01) :221-231
[8]   POST-NEWTONIAN HYDRODYNAMICS AND POST-NEWTONIAN GRAVITATIONAL-WAVE GENERATION FOR NUMERICAL RELATIVITY [J].
BLANCHET, L ;
DAMOUR, T ;
SCHAFER, G .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1990, 242 (02) :289-305
[9]   ROTATING FLUID MASSES IN GENERAL RELATIVITY [J].
BOYER, RH .
PROCEEDINGS OF THE CAMBRIDGE PHILOSOPHICAL SOCIETY-MATHEMATICAL AND PHYSICAL SCIENCES, 1965, 61 :527-&
[10]   Numerical evolution of matter in dynamical axisymmetric black hole spacetimes -: I.: Methods and tests [J].
Brandt, S ;
Font, JA ;
Ibáñez, JM ;
Massó, J ;
Seidel, E .
COMPUTER PHYSICS COMMUNICATIONS, 2000, 124 (2-3) :169-196