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arXiv · 0905.4440

Accretion of a massive magnetized torus on a rotating black hole

Maxim V. Barkov·Anton N. Baushev
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Abstract

We present numerical simulations of the axisymmetric accretion of a massive magnetized plasma torus on a rotating black hole. We use a realistic equation of state, which takes into account neutrino cooling and energy loss due to nucleus dissociations. We simulated various magnetic field configurations and torus models, both optically thick and thin for neutrinos. It is shown that the neutrino cooling does not significantly change either the structure of the accretion flow or the total energy release of the system. The calculations evidence heating of the wind surrounding the collapsar by the shock waves generated at the jet-wind border. This mechanism can give rise to a hot corona around the binary system like SS433. Angular momentum of the accreting matter defines the time scale of the accretion. Due to the absence of the magnetic dynamo in our calculations, the initial strength and topology of the magnetic field determines magnetization of the black hole, jet formation properties and the total energy yield. We estimated the total energy transformed to jets as $1.3\times 10^{52}$ {ergs} which was sufficient to explain hypernova explosions like GRB 980425 or GRB 030329.

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Maxim V. Barkov, Anton N. Baushev. 2009-05-27. Accretion of a massive magnetized torus on a rotating black hole. https://doi.org/10.1016/j.newast.2010.07.001

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