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arXiv · 0904.1007

Redshift Evolution in the Iron Abundance of the Intracluster Medium

Michael E. Anderson·Joel N. Bregman·Suzanne C. Butler·C. R. Mullis
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Abstract

Clusters of galaxies provide a closed box within which one can determine the chemical evolution of the gaseous baryons with cosmic time. We studied this metallicity evolution in the hot X-ray emitting baryons through an analysis of XMM-Newton observations of 29 galaxy clusters in the redshift range 0.3 < z < 1.3. Taken alone, this data set does not show evidence for significant evolution. However, when we also include a comparable sample of 115 clusters observed with Chandra (Maughan et al. 2008) and a lower redshift sample of 70 clusters observed with XMM at z < 0.3 (Snowden et al. 2008), there is definitive evidence for a decrease in the metallicity. This decrease is approximately a factor of two from z = 0 to z \approx 1, over which we find a least-squares best-fit line Z(z) / Z_{\odot} = (0.46 \pm 0.05) - (0.38 \pm 0.03)z. The greatest uncertainty in the evolution comes from poorly constrained metallicities in the highest redshift bin.

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Michael E. Anderson, Joel N. Bregman, Suzanne C. Butler, C. R. Mullis. 2009-04-06. Redshift Evolution in the Iron Abundance of the Intracluster Medium. https://doi.org/10.1088/0004-637x%2F698%2F1%2F317

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