Discovery of depressions in the X-ray emission of the distant galaxy cluster RBS797 in a CHANDRA observation

Abstract

We present CHANDRA observations of the X-ray luminous, distant galaxy cluster RBS797 at z=0.35. In the central region the X-ray emission shows two pronounced X-ray minima, which are located opposite to each other with respect to the cluster centre. These depressions suggest an interaction between the central radio galaxy and the intra-cluster medium, which would be the first detection in such a distant cluster. The minima are symmetric relative to the cluster centre and very deep compared to similar features found in a few other nearby clusters. A spectral and morphological analysis of the overall cluster emission shows that RBS797 is a hot cluster (T=7.7^{+1.2}_{-1.0} keV) with a total mass of M_{tot}(r_{500})=6.5^{+1.6}_{-1.2} 10^{14} \msol.