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arXiv · 2404.08267

An XRISM observation proposal: Gas velocity in the merging cluster Abell 2256

Takayuki Tamura
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Abstract

One of the XRISM mission goals is to measure the gas dynamics of galaxy clusters with Resolve spectroscopy. To archive these, we propose an observation of the X-ray bright galaxy cluster Abell 2256 at z=0.06. This hosts 2nd brightest diffuse radio relic. Suzaku revealed a gas bulk motion at 1500 km/s, for the first time i\ n a cluster. This X-ray gas velocity is consistent with those measured in galaxy velocities, indicating that gas and galaxies are moving together. These and other observations make this system the most suitable for the XRISM spectral mapping of gas bulk and tur\ bulent motions and related physics. We propose two pointings to cover the central ~400kpc region.

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Takayuki Tamura. 2024-04-12. An XRISM observation proposal: Gas velocity in the merging cluster Abell 2256. https://arxiv.org/abs/2404.08267

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