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arXiv · 1207.3729

The first measurement of temperature standard deviation along the line-of-sight in galaxy clusters

D. A. Prokhorov·S. Colafrancesco
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Abstract

Clusters of galaxies are mainly formed by merging of smaller structures, according to the standard cosmological scenario. If the mass of a substructure is >10% of that of a galaxy cluster, the temperature distribution of the intracluster medium (ICM) in a merging cluster becomes inhomogeneous. Various methods have been used to derive the two-dimensional projected temperature distribution of the ICM. However, methods for studying temperature distribution along the line-of-sight through the cluster were absent. In this paper, we present the first measurement of the temperature standard deviation along the line-of-sight, using as a reference case the multifrequency SZ measurements of the Bullet Cluster. We find that the value of the temperature standard deviation is high and equals to (10.6+/-3.8) keV in the Bullet Cluster. This result shows that the temperature distribution in the Bullet Cluster is strongly inhomogeneous along the line-of-sight and provides a new method for studying galaxy clusters in depth.

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D. A. Prokhorov, S. Colafrancesco. 2012-07-16. The first measurement of temperature standard deviation along the line-of-sight in galaxy clusters. https://doi.org/10.1111/j.1745-3933.2012.01284.x

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