Open AccessDynamics of magnetized relativistic tori oscillating around black holes
Author(s) -
Montero P. J.,
Zanotti O.,
Font J. A.,
Rezzolla L.
Publication year - 2007
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2007.11844.x
Subject(s) - physics , torus , angular momentum , magnetic field , astrophysics , schwarzschild radius , toroid , classical mechanics , oscillation (cell signaling) , black hole (networking) , rotating black hole , gravitation , quantum electrodynamics , plasma , quantum mechanics , computer network , routing protocol , geometry , mathematics , routing (electronic design automation) , biology , computer science , genetics , link state routing protocol
We present a numerical study of the dynamics of magnetized, relativistic, non‐self‐gravitating, axisymmetric tori orbiting in the background space–times of Schwarzschild and Kerr black holes. The initial models have a constant specific angular momentum and are built with a non‐zero toroidal magnetic field component, for which equilibrium configurations have recently been obtained. In this work we extend our previous investigations which dealt with purely hydrodynamical thick discs, and study the dynamics of magnetized tori subject to perturbations which, for the values of the magnetic field strength considered here, trigger quasi‐periodic oscillations lasting for tens of orbital periods. Overall, we have found that the dynamics of the magnetized tori analysed is very similar to that found in the corresponding unmagnetized models. The spectral distribution of the eigenfrequencies of oscillation shows the presence of a fundamental p mode and of a series of overtones in a harmonic ratio 2:3: … . These simulations, therefore, extend the validity of the model of Rezzolla et al. for explaining the high‐frequency QPOs observed in the spectra of low‐mass X‐ray binaries containing a black hole candidate also to the case of magnetized discs with purely toroidal magnetic field distribution. If sufficiently compact and massive, these oscillations can also lead to the emission of intense gravitational radiation which is potentially detectable for sources within the Galaxy.