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arXiv · 1605.06133

XMMSL1J063045.9-603110: a tidal disruption event fallen into the back burner

Deborah Mainetti·Sergio Campana·Monica Colpi
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Abstract

Black holes at the centre of quiescent galaxies can be switched on when they accrete gas that is gained from stellar tidal disruptions. A star approaching a black hole on a low angular momentum orbit may be ripped apart by tidal forces, which triggers raining down of a fraction of stellar debris onto the compact object through an accretion disc and powers a bright flare. In this paper we discuss XMMSL1J063045.9-603110 as a candidate object for a tidal disruption event. The source has recently been detected to be bright in the soft X-rays during an XMM-Newton slew and later showed an X-ray flux decay by a factor of about 10 in twenty days. We analyse XMM-Newton and Swift data. XMMSL1J063045.9-603110 shows several features typical of tidal disruption events: the X-ray spectrum shows the characteristics of a spectrum arising from a thermal accretion disc, the flux decay follows a t^-5/3 law, and the flux variation is > 350. Optical observations testify that XMMSL1J063045.9-603110 is probably associated with an extremely small galaxy or even a globular cluster, which suggests that intermediate-mass black holes are located in the cores of (at least) some of them.

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Deborah Mainetti, Sergio Campana, Monica Colpi. 2016-05-19. XMMSL1J063045.9-603110: a tidal disruption event fallen into the back burner. https://doi.org/10.1051/0004-6361%2F201628737

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