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Super-Eddington accretion disc around a Kerr black hole

Andrei M. Beloborodov
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Abstract

We calculate the structure of accretion disc around a rapidly rotating black hole with a super-Eddington accretion rate. The luminosity and height of the disc are reduced by the advection effect. In the case of a large viscosity parameter, alpha > 0.03, the accretion flow strongly deviates from thermodynamic equilibrium and overheats in the central region. With increasing accretion rate, the flow temperature steeply increases, reaches a maximum, and then falls off. The maximum is achieved in the advection dominated regime of accretion. The maximum temperature in the disc around a massive black hole, M=10^8 M_sun, with alpha=0.3 is of order 3 x 10^8 K. Discs with large accretion rates can emit X-rays in quasars as well as in galactic black hole candidates.

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Andrei M. Beloborodov. 1998-02-11. Super-Eddington accretion disc around a Kerr black hole. https://doi.org/10.1046/j.1365-8711.1998.01530.x

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