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Activity From Tidal Disruptions in Galactic Nuclei

Kristen Menou·Eliot Quataert
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Abstract

The tidal disruption of a star by a supermassive black hole is expected to lead to a short bright flare followed by an extended period of low-level emission. Existing models of the late-time accretion of the stellar debris via a thin disk imply that the Galactic Center source Sgr A* should be brighter than currently observed by several orders of magnitude. A similar problem exists for M31 and M32. This problem could be avoided if thin disk accretion transitions to low radiative efficiency accretion (e.g., ADAF, CDAF) at low accretion rates (via ``evaporation'' of the thin disk). Alternatively, we show that the outer portions of a thin disk may become neutral and unable to sustain MHD turbulence on a timescale less than the time between tidal disruption events; this may dramatically shorten the duration of the late accretion phase.

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Kristen Menou, Eliot Quataert. 2001-11-14. Activity From Tidal Disruptions in Galactic Nuclei. https://doi.org/10.1086/338195

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