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arXiv · 1109.5688

Intracluster medium of the merging cluster Abell 3395

K. Lakhchaura·K. P. Singh·D. J. Saikia·R. W. Hunstead
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Abstract

We present a detailed imaging and spectral analysis of the merging environment of the bimodal cluster A3395 using X-ray and radio observations. X-ray images of the cluster show five main constituents of diffuse emission : A3395 NE, A3395 SW, A3395 NW, A3395 W, and a filament connecting NE to W. X-ray surface-brightness profiles of the cluster did not show any shock fronts in the cluster. Temperature and entropy maps show high temperature and high entropy regions in the W, the NW, the filament and between the NE and SW subclusters. The NE, SW and W components have X-ray bolometric luminosities similar to those of rich clusters of galaxies but have relatively higher temperatures. Similarly, the NW component has X-ray bolometric luminosity similar to that of isolated groups but with much higher temperature. It is, therefore, possible that all the components of the cluster have been heated by the ongoing mergers. The NE subcluster is the most massive and luminous constituent and other subclusters are found to be gravitationally bound to it. The W component is most probably either a clump of gas stripped off the SW due to ram pressure or a separate subcluster that has merged or is merging with the SW. No X-ray cavities are seen associated with the Wide Angle Tailed (WAT) radio source near the centre of the SW subcluster. Minimum energy pressure in the radio emission-peaks of the WAT galaxy is comparable with the external thermal pressure. The radio spectrum of the WAT suggests a spectral age of ~10Myr.

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K. Lakhchaura, K. P. Singh, D. J. Saikia, R. W. Hunstead. 2011-09-26. Intracluster medium of the merging cluster Abell 3395. https://doi.org/10.1088/0004-637x%2F743%2F1%2F78

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