The history of chemical enrichment in the intracluster medium from
  cosmological simulations
  The distribution of metals in the intracluster medium (ICM) of galaxy
clusters provides valuable information on their formation and evolution, on the
connection with the cosmic star formation and on the effects of different gas
processes. By analyzing a sample of simulated galaxy clusters, we study the
chemical enrichment of the ICM, its evolution, and its relation with the
physical processes included in the simulation and with the thermal properties
of the core. These simulations, consisting of re-simulations of 29 Lagrangian
regions performed with an upgraded version of the SPH GADGET-3 code, have been
run including two different sets of baryonic physics: one accounts for
radiative cooling, star formation, metal enrichment and supernova (SN)
feedback, and the other one further includes the effects of feedback from
active galactic nuclei (AGN). In agreement with observations, we find an
anti-correlation between entropy and metallicity in cluster cores, and similar
radial distributions of heavy-element abundances and abundance ratios out to
large cluster-centric distances (~R180). In the outskirts, namely outside of
~0.2R180, we find a remarkably homogeneous metallicity distribution, with
almost flat profiles of the elements produced by either SNIa or SNII. We
investigated the origin of this phenomenon and discovered that it is due to the
widespread displacement of metal-rich gas by early (z>2-3) AGN powerful bursts,
acting on small high-redshift haloes. Our results also indicate that the
intrinsic metallicity of the hot gas for this sample is on average consistent
with no evolution between z=2 and z=0, across the entire radial range.
