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arXiv · 1212.5267

Prompt Emission from Tidal Disruptions of White Dwarfs by Intermediate Mass Black Holes

Roman V. Shcherbakov·Asaf Pe'er·Christopher S. Reynolds·Roland Haas·Tanja Bode·Pablo Laguna
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Abstract

We present a qualitative picture of prompt emission from tidal disruptions of white dwarfs (WD) by intermediate mass black holes (IMBH). The smaller size of an IMBH compared to a supermassive black hole and a smaller tidal radius of a WD disruption lead to a very fast event with high peak luminosity. Magnetic field is generated in situ following the tidal disruption, which leads to effective accretion. Since large-scale magnetic field is also produced, geometrically thick super-Eddington inflow leads to a relativistic jet. The dense jet possesses a photosphere, which emits quasi-thermal radiation in soft X-rays. The source can be classified as a long low-luminosity gamma-ray burst (ll-GRB). Tidal compression of a WD causes nuclear ignition, which is observable as an accompanying supernova. We suggest that GRB060218 and SN2006aj is such a pair of ll-GRB and supernova. We argue that in a flux-limited sample the disruptions of WDs by IMBHs are more frequent then the disruptions of other stars by IMBHs.

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Roman V. Shcherbakov, Asaf Pe'er, Christopher S. Reynolds, Roland Haas, Tanja Bode, Pablo Laguna. 2012-12-20. Prompt Emission from Tidal Disruptions of White Dwarfs by Intermediate Mass Black Holes. https://doi.org/10.1051/epjconf%2F20123902007

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