The identification of an optical counterpart to the super-Eddington X-ray source NGC 5204 X-1

Roberts, T.P.; Goad, M.R.; Ward, M.J.; Warwick, R.S.; O'Brien, P.T.; Lira, P.; Hands, A.D.P.

Abstract

We report the identification of a possible optical counterpart to the super-Eddington X-ray source NGC 5204 X-1. New Chandra data show that the X-ray source is point-like, with a luminosity of 5.2×10^39 erg/s (0.5-8 keV). It displays medium- and long-term X-ray variability in observations spanning a period of 20yr. The accurate Chandra position allows us to identify a blue optical continuum source (mv=19.7) at the position of NGC 5204 X-1, using newly obtained optical data from the INTEGRAL instrument on the William Herschel Telescope. The X-ray and optical source properties are consistent with the scenario in which we are observing the beamed X-ray emission of a high-mass X-ray binary in NGC 5204, composed of an O star with either a black hole or neutron star companion.

Citation

Roberts, T., Goad, M., Ward, M., Warwick, R., O'Brien, P., Lira, P., & Hands, A. (2001). The identification of an optical counterpart to the super-Eddington X-ray source NGC 5204 X-1. Monthly Notices of the Royal Astronomical Society, 325(2), L7-L11. https://doi.org/10.1046/j.1365-8711.2001.04659.x

• Journal Article Type: Article
• Publication Date: 2001-08
• Deposit Date: Apr 16, 2008
• Publicly Available Date: Aug 8, 2014
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 325
• Issue: 2
• Pages: L7-L11
• DOI: https://doi.org/10.1046/j.1365-8711.2001.04659.x
• Keywords: High-resolution imager, All-sky survey, Rosat observations, Nearby galaxies, Emission, Sample.