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arXiv · 1709.03964

On the Papaloizou-Pringle instability in tidal disruption events

Rebecca Nealon·Daniel J. Price·Clément Bonnerot·Giuseppe Lodato
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Abstract

We demonstrate that the compact, thick disc formed in a tidal disruption event may be unstable to non-axisymmetric perturbations in the form of the Papaloizou-Pringle instability. We show this can lead to rapid redistribution of angular momentum that can be parameterised in terms of an effective Shakura-Sunyaev $α$ parameter. For remnants that have initially weak magnetic fields, this may be responsible for driving mass accretion prior to the onset of the magneto-rotational instability. For tidal disruptions around a $10^6$ M$_{\odot}$ black hole, the measured accretion rate is super-Eddington but is not sustainable over many orbits. We thus identify a method by which the torus formed in tidal disruption event may be significantly accreted before the magneto-rotational instability is established.

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Rebecca Nealon, Daniel J. Price, Clément Bonnerot, Giuseppe Lodato. 2017-11-03. On the Papaloizou-Pringle instability in tidal disruption events. https://doi.org/10.1093/mnras%2Fstx2871

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