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arXiv · 1212.1140

PS1-10jh - a tidal disruption event with an extremely low disk temperature

Abstract

The cooler than expected optical-UV transient PS1-10jh detected by the Pan-STARRS1 survey is probably related to a tidal disruption event in which a He-rich stellar core remnant is implied. The evolution of bound debris during the disk phase is studied by solving the hydrodynamic equations. The model provides a good fit either of the raising part of the light curve in the bands g_(P1), r_(P1), and i_(P1) or in the early decay. The parameters characterizing this optimized model are the mass of the central black hole, i.e., 6.3x10^6 Msun and the critical Reynolds number Re = 10^4 that fixes the viscosity and the accretion timescale. Such a high value of Re explains the low disk temperature and the consequent absence of X-ray emission. The predicted bolometric peak luminosity is about 10^45 erg/s and the predicted total radiated energy is about Erad=2.67x10^(51) erg.

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Matias Montesinos, J. A. de Freitas Pacheco. 2012-12-05. PS1-10jh - a tidal disruption event with an extremely low disk temperature. https://doi.org/10.1093/mnrasl%2Fsls047

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