Aims. We aim to provide constraints on evolutionary scenarios in clusters. One of our main goals is to understand whether, as claimed by some, the cool core/non-cool core division is established once and for all during the early history of a cluster.
Methods. We employ a sample of about 60 objects to classify clusters according to different properties: we characterize cluster cores in terms of their thermo-dynamic and chemical properties and clusters as a whole in terms of their dynamical properties. Results. We find that: I) the vast majority of merging systems feature high entropy cores (HEC); II) objects with lower entropy cores feature more pronounced metallicity peaks than objects with higher entropy cores. We identify a small number of medium (MEC) and high (HEC) entropy core systems which, unlike most other such objects, feature a large central metallicity. The majority of these outliers are mergers, i.e. systems far from their equilibrium configuration. Conclusions. We surmise that medium (MEC) and high (HEC) entropy core systems with a large central metallicity recently evolved from low entropy core (LEC) clusters that have experienced a heating event associated to AGN or merger activity.
We employ a long XMM-Newton observation of the core of the Perseus cluster to validate claims of a non-thermal component discovered with Chandra. From a meticulous analysis of our dataset, which includes a detailed treatment of systematic errors, we
find the 2-10 keV surface brightness of the non-thermal component to be smaller than about 5x10^-16 erg cm^-2s^-1arcsec^-2. The most likely explanation for the discrepancy between the XMM-Newton and Chandra estimates is a problem in the effective area calibration of the latter. Our EPIC based magnetic field lower limits are not in disagreement with Faraday rotation measure estimates on a few cool cores and with a minimum energy estimate on Perseus. In the not too distant future Simbol-X may allow detection of non-thermal components with intensities more than 10 times smaller than those that can be measured with EPIC; nonetheless even the exquisite sensitivity within reach for Simbol-X might be insufficient to detect the IC emission from Perseus.