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XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204 X-1

T. P. Roberts·R. S. Warwick·M. J. Ward·M. R. Goad·L. P. Jenkins
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Abstract

We present the results of two XMM-Newton observations of the ultraluminous X-ray source (ULX) NGC 5204 X-1. The EPIC spectra are well-fit by the standard spectral model of a black-hole X-ray binary, comprising a soft multi-colour disc blackbody component plus a harder power-law continuum. The cool (kT_in ~ 0.2 keV) inner-disc temperature required by this model favours the presence of an intermediate-mass black hole (IMBH) in this system, though we highlight a possible anomaly in the slope of the power-law continuum in such fits. We discuss the interpretation of this and other, non-standard spectral modelling of the data.

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T. P. Roberts, R. S. Warwick, M. J. Ward, M. R. Goad, L. P. Jenkins. 2004-12-20. XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204 X-1. https://doi.org/10.1111/j.1365-2966.2005.08758.x

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