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arXiv · 1004.3102

Influence of self-gravity on the runaway instability of black hole-torus systems

Pedro J. Montero·Jose A. Font·Masaru Shibata
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Abstract

Results from the first fully general relativistic numerical simulations in axisymmetry of a system formed by a black hole surrounded by a self-gravitating torus in equilibrium are presented, aiming to assess the influence of the torus self-gravity on the onset of the runaway instability. We consider several models with varying torus-to-black hole mass ratio and angular momentum distribution orbiting in equilibrium around a non-rotating black hole. The tori are perturbed to induce the mass transfer towards the black hole. Our numerical simulations show that all models exhibit a persistent phase of axisymmetric oscillations around their equilibria for several dynamical timescales without the appearance of the runaway instability, indicating that the self-gravity of the torus does not play a critical role favoring the onset of the instability, at least during the first few dynamical timescales.

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Pedro J. Montero, Jose A. Font, Masaru Shibata. 2010-04-19. Influence of self-gravity on the runaway instability of black hole-torus systems. https://doi.org/10.1103/physrevlett.104.191101

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