Self-similarity of temperature profiles in distant galaxy clusters: The quest for a universal law

Abstract

Context. We present the XMM-Newton temperature profiles of 12 bright (L X > 4 × 10 44 erg s -1) clusters of galaxies at 0.4 < z < 0.9, having an average temperature in the range 5 < z < 0.9). A comparison of our high-z sample with intermediate clusters at 0.1 < z < 0.3 showed how the CC and NCC cluster temperature profiles have experienced some sort of evolution. This can happen because higher z clusters are at a less advanced stage of their formation and did not have enough time to create a relaxed structure, which is characterized by a central temperature dip in CC clusters and by flatter profiles in NCC clusters. Conclusions. This is the first time that a systematic study of the temperature profiles of galaxy clusters at z > 0.4 has been attempted. We were able to define the closest possible relation to a universal law for the temperature profiles of galaxy clusters at 0.1 < z < 0.9, showing a dependence on both the relaxation state of the clusters and the redshift. © 2012 ESO.