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arXiv · 1301.1852

Bulk motion measurements in clusters of galaxies with ATHENA-like missions

J. Nevalainen
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Abstract

The hierarchical formation of clusters of galaxies by accretion of material releases gravitational energy which dissipates into the intracluster gas. The process heats the material and generates gas turbulence and bulk motions and thus kinetic pressure. Mapping the velocity fields of the moving subunits would enable a new diagnostics tool for cluster formation studies and unbiased X-ray mass estimates. The required spatially resolved high resolution spectroscopy is not currently available. I demonstrate here the feasibility of detecting and mapping the velocities of the bulk motions using the Doppler shift of the Fe XXV K alpha line with the proposed ATHENA satellite.

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J. Nevalainen. 2013-01-09. Bulk motion measurements in clusters of galaxies with ATHENA-like missions. https://doi.org/10.1002/asna.201211849

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