IC 1262 and NGC 6159 have been selected for high resolution observations because their X-ray luminosity observed in the ROSAT All Sky Survey (Voges 1992) was higher than that observed from other normal, early type galaxies. The HRI observations confirm both the identification of the X-ray sources with the two galaxies (see Fig. 1; point sources in the field, clearly associated with optical counterparts, further ensure that the absolute pointing is correct), and the very high luminosities. Moreover, they indicate very extended emission, out to ≥ 7′ and ≥ 4′ radius (≥ 400 and ≥ 220 kpc at the galaxies’ distances), respectively, with a relatively regular morphology (although not azimuthally symmetric at large radii), and a smoothly decreasing surface brightness profile. At the center of IC 1262, however, several peculiar features are present (see Fig. 3 and later discussion).
The mergers in Abell 2256: displaced gas and its connection to the radio-emitting plasma