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arXiv · 1101.1849

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

Kyoko Matsushita
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Abstract

Aims.The abundances of Fe in the intracluster medium of nearby (z<0.08) clusters were measured up to 0.3$\sim$ 0.5r$_{180}$. 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 0.1$r_{180}$, and at 0.1--0.3$r_{180}$, they have flatter Fe abundance profiles at 0.4$\sim$0.5 solar, with a small scatter. Most other clusters, including merging clusters, also have similar Fe abundance profiles beyond 0.1$r_{180}$. 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.

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Kyoko Matsushita. 2011-01-10. Radial profiles of Fe abundance in the intracluster medium of nearby clusters observed with XMM-Newton. https://doi.org/10.1051/0004-6361/200913432

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