Radial profiles of Fe abundance in the intracluster medium of nearby clusters observed with XMM-Newton

Department of PhysicsTokyo University of Science, 1−3 Kagurazaka, Shinjyuku-ku, Tokyo 162-8601, Japan
e-mail: matusita@rs.kagu.tus.ac.jp

Received: 9 October 2009
Accepted: 5 January 2011

Abstract

Aims. The abundances of Fe in the intracluster medium of nearby (z < 0.08) clusters were measured up to 0.3 ~ 0.5r₁₈₀.

Methods. We analyzed 28 clusters of galaxies observed with XMM-Newton. We derived Fe abundances from the flux ratios of Fe lines to the continuum within an energy range of 3.5−6 keV to minimize and evaluate systematic uncertainties.

Results. The radial profiles of the Fe abundances of relaxed clusters with a cD galaxy at their X-ray peak have similar slopes. These clusters show similar enhancements in the Fe abundance within 0.1r₁₈₀, and at 0.1−0.3r₁₈₀, they have flatter Fe abundance profiles at 0.4 ~ 0.5 solar, with a small scatter. Most other clusters, including merging clusters, also have similar Fe abundance profiles beyond 0.1r₁₈₀.These clusters may have universal metal enrichment histories, and a significant amount of Fe was synthesized at a very early stage in cluster formation. Mergers of clusters can destroy the central Fe peak.