Letter to the Editor

Metal enrichment processes in the intra-cluster medium

¹ Institut für Astrophysik, Leopold-Franzens Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria http://astro.uibk.ac.at/astroneu/hydroskiteam/index.htm e-mail: sabine.schindler@uibk.ac.at
² School of Mathematics, University of Edinburgh, Edinburgh EH9 3JZ, Scotland, UK
³ Institut für Astronomie, Universität Wien, Türkenschanzstr. 17, 1180 Vienna, Austria

Received: 11 February 2005
Accepted: 6 April 2005

Abstract

We present numerical simulations of galaxy clusters which include interaction processes between the galaxies and the intra-cluster gas. The considered interaction processes are galactic winds and ram-pressure stripping, which both transfer metal-enriched interstellar medium into the intra-cluster gas and hence increase its metallicity. We investigate the efficiency and time evolution of the interaction processes by simulated metallicity maps, which are directly comparable to those obtained from X-ray observations. We find that ram-pressure stripping is more efficient than quiet (i.e. non-starburst driven) galactic winds in the redshift interval between 1 and 0. The expelled metals are not mixed immediately with the intra-cluster gas, but inhomogeneities are visible in the metallicity maps. Even stripes of higher metallicity that a single galaxy has left behind can be seen. The spatial distribution of the metals transported by ram-pressure stripping and by galactic winds are very different for massive clusters: the former process yields a centrally concentrated metal distribution while the latter results in an extended metal distribution.