Deep XMM-Newton and Chandra observations of Cl J1226.9+3332: A detailed X-ray mass analysis of a z=0.89 galaxy cluster

Deep XMM-Newton and Chandra observations of Cl J1226.9+ 3332 at z = 0: 89 have enabled the most detailed X-ray mass analysis of any such high-redshift galaxy cluster. The XMM-Newton temperature profile of the system shows no sign of central cooling, with a hot core and a radially declining profile. A temperature map shows asymmetry with a hot region that appears to be associated with a subclump of galaxies at the cluster redshift but is not visible in the X-ray surface brightness. This is likely to be the result of a merger event in the cluster but does not appear to significantly affect the overall temperature profile. The XMM-Newton temperature profile and combined Chandra and XMM-Newton emissivity profile allowed precise measurements of the global properties of Cl J1226.9+3332. Within an overdensity radius of 500 times the critical density at z = 0.89 (R-500), we find kT 10.4 +/- 0.6 keV, Z = 0.16 +/- 0.05 Z(circle dot), and M = 5.2(-0.8)(+1.0) x 10(14) M-circle dot. We obtain profiles of the metallicity, entropy, cooling time, and gas fraction and find a high concentration parameter for the total density profile of the system. The global properties are compared with the local L-T and M- T relations, and we are able to make the first observational test of the predicted evolution of the Y-X-M-500 relation. We find that departures from these scaling relations are most likely caused by an underestimate of the total mass by similar to 30% in the X-ray hydrostatic mass analysis due to the apparent recent or ongoing merger activity.