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arXiv · 1412.4561

Local Stability of Strongly Magnetized Black Hole Tori

Maciek Wielgus·P. Chris Fragile·Ziming Wang·Julia Wilson
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Abstract

We investigate the local stability of strongly magnetized relativistic tori orbiting Kerr black holes, for the case of a purely toroidal magnetic field topology. Our approach encompasses both solving the full dispersion relation numerically and solving a simplified analytic treatment. Both approaches indicate that such tori are subject to an unstable non-axisymmetric magnetorotational mode, regardless of such background properties as the gas-to-magnetic pressure ratio and specific angular momentum distribution. We demonstrate that our modal analysis matches well with what is seen in global, three-dimensional, general relativistic magnetohydrodynamic simulations.

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Maciek Wielgus, P. Chris Fragile, Ziming Wang, Julia Wilson. 2014-12-15. Local Stability of Strongly Magnetized Black Hole Tori. https://doi.org/10.1093/mnras%2Fstu2676

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