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Temperature and Heavy Element Abundance Profiles of Cool Clusters of Galaxies from ASCA

A. Finoguenov·M. Arnaud·L. P. David
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Abstract

We perform a spatially resolved X-ray spectroscopic study of a set of 18 relaxed clusters of galaxies with gas temperatures below 4 keV. Spectral analysis was done using ASCA/SIS data coupled with the spatial information contained in ROSAT/PSPC and Einstein/IPC observations. We derive the temperature profiles using single-temperature fits and also correct for the presence of cold gas at the cluster centers. For all of the clusters in the sample, we derive Si and Fe abundance profiles. For a few of the clusters, we also derive Ne and S abundance profiles. We present a comparison of the elemental abundances derived at similar overdensities as well as element mass-to-light ratios. We conclude that the preferential accretion of low entropy, low abundance gas into the potentials of groups and cold clusters can explain most of the observed trends in metallicity. In addition, we discuss the importance of energy input from SNe II on cluster scaling relations and on the relation between the observed scatter in the retainment of SN Ia products with differences between the epoch of cluster formation.

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A. Finoguenov, M. Arnaud, L. P. David. 2001-03-28. Temperature and Heavy Element Abundance Profiles of Cool Clusters of Galaxies from ASCA. https://doi.org/10.1086/321457

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