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arXiv · 1211.0831

The accretion disc, jets and environment of the intermediate mass black hole candidate ESO 243-49 HLX-1

N. A. Webb·D. Barret·V. Braito·S. Corbel·D. Cseh·S. A. Farrell·R. P. Fender·N. Gehrels·O. Godet·I. Heywood·T. Kawaguchi·J. -P. Lasota·E. Lenc·D. Lin·B. Plazolles·M. Servillat
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Abstract

The Ultra Luminous X-ray (ULX) source HLX-1 in the galaxy ESO 243-49 has an observed maximum unabsorbed X-ray luminosity of 1.3e42 erg/s (0.2-10.0 keV). From the conservative assumption that this value exceeds the Eddington limit by at most a factor of 10, the minimum mass is then 500 solar masses. The X-ray luminosity varies by a factor of 40 with an apparent recurrence timescale of approximately one year. This X-ray variability is associated with spectral state transitions similar to those seen in black hole X-ray binaries. Here we discuss our recent modelling of all the X-ray data for HLX-1 and show that it supports the idea that this ULX is powered by sub- and near Eddington accretion onto an intermediate mass black hole. We also present evidence for transient radio emission which is consistent with a discrete jet ejection event as well as comment on the nature of the environment around HLX-1 in light of recent Hubble Space Telescope photometry.

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N. A. Webb, D. Barret, V. Braito, S. Corbel, D. Cseh, S. A. Farrell, R. P. Fender, N. Gehrels, O. Godet, I. Heywood, T. Kawaguchi, J. -P. Lasota, E. Lenc, D. Lin, B. Plazolles, M. Servillat. 2012-11-05. The accretion disc, jets and environment of the intermediate mass black hole candidate ESO 243-49 HLX-1. https://arxiv.org/abs/1211.0831

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