The X-ray properties of the low-redshift quasar MRC 2251-178 and its environment: some surprises

MR 2251-178 was the first quasar initially discovered in X-rays, and the first one found to host a warm absorber. Despite its many outstanding multi-wavelength properties, MR 2251-178 has not yet been studied in detail with recent X-ray observatories. Here, we present results from an analysis of the X-ray spectral, temporal, and spatial properties of this source and its environment based on deep observations carried out with the X-ray satellite {\sl ROSAT}. The derived mean soft X-ray luminosity of MR 2251-178, ~10^{45} erg/s, places the quasar among the most X-ray luminous AGN in the local universe. The complete results of this study appeared in A&A 367, 801 (see http://www.xray.mpe.mpg.de/~skomossa/).