Simulations of galactic winds and starbursts in galaxy clusters

School of Mathematics, University of Edinburgh, Edinburgh EH9 3JZ, Scotland, UK-/-Abstract. We present an investigation of the metal enrichmentof the intra-cluster medium (ICM) bygalactic windsand merger-driven starbursts. We use combined N-body/hydrodynamic simulations with a semi-numerical galaxyformation model. The mass loss by galactic winds is obtained by calculating transonic solutions of steady stateoutflows, driven by thermal, cosmic ray and MHD wave pressure. The inhomogeneities in the metal distributioncaused by these processes are an ideal tool to reveal the dynamical state of a galaxy cluster. We present surfacebrightness, X-ray emission weighted temperature and metal maps of our model clusters as they would be observedby X-ray telescopes like XMM-Newton. We show that X-ray weighted metal maps distinguish between pre- orpost-merger galaxy clusters by comparing the metallicity distribution with the galaxy-density distribution: pre-mergers have a metallicity gap between the subclusters, post-mergers a high metallicity between subclusters. Weapply our approach to two observed galaxy clusters, Abell 3528 and Abell 3921, to show whether they are pre-or post-merging systems. The survival time of the inhomogeneities in the metallicity distribution found in oursimulations is up to several Gyr. We show that galactic winds and merger-driven starbursts enrich the ICM veryefficiently after z=1 in the central (∼ 3 Mpc radius) region of a galaxy cluster.Key words. Galaxies: clusters: general - Galaxies: abundances - Galaxies: interactions - Galaxies: ISM - X-ray:galaxies: clusters