XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204   X-1
  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. 
T. P. Roberts (1), R. S. Warwick (1), M. J. Ward (1 and 2), M. R. Goad   (1 and 3), L. P. Jenkins (1) ((1) University of Lei...