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arXiv · 1410.1500

An X-ray and UV flare from the galaxy XMMSL1 J061927.1-655311

R. D. Saxton·A. M. Read·S. Komossa·P. Rodriguez-Pascual·G. Miniutti·P. Dobbie·P. Esquej·M. Colless·K. W. Bannister
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Abstract

New high variability extragalactic sources may be identified by comparing the flux of sources seen in the XMM-Newton Slew Survey with detections and upper limits from the ROSAT All Sky Survey. In November 2012, X-ray emission was detected from the galaxy XMMSL1 J061927.1-655311 (a.k.a. 2MASX 06192755-6553079), a factor 140 times higher than an upper limit from 20 years earlier. Both the X-ray and UV flux subsequently fell, over the following year, by factors of 20 and 4 respectively. Optically, the galaxy appears to be a Seyfert I with broad Balmer lines and weak, narrow, low-ionisation emission lines, at a redshift of 0.0729. The X-ray luminosity peaks at Lx ~ 8x10^43 ergs/s with a typical Sy I-like power-law X-ray spectrum of index ~ 2. The flare has either been caused by a tidal disruption event or by an increase in the accretion rate of a persistent AGN.

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R. D. Saxton, A. M. Read, S. Komossa, P. Rodriguez-Pascual, G. Miniutti, P. Dobbie, P. Esquej, M. Colless, K. W. Bannister. 2014-09-22. An X-ray and UV flare from the galaxy XMMSL1 J061927.1-655311. https://doi.org/10.1051/0004-6361%2F201424347

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