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arXiv · 1904.08803

A merger shock in Abell 1367

Chong Ge·Ming Sun·Ruo-Yu Liu·Lawrence Rudnick·Craig Sarazin·William Forman·Christine Jones·Hao Chen·Wenhao Liu·Masafumi Yagi·Alessandro Boselli·Matteo Fossati·Giuseppe Gavazzi
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Abstract

Multi-wavelength observations show that Abell 1367 (A1367) is a dynamically young cluster, with at least two subclusters merging along the SE-NW direction. With the wide-field XMM-Newton mosaic of A1367, we discover a previously unknown merger shock at the NW edge of the cluster. We estimate the shock Mach number from the density and temperature jumps as $M_ρ=1.21\pm0.08$ and $M_T=1.60\pm0.07$, respectively. This shock region also corresponds to a radio relic discovered with the VLA and GBT, which could be produced by the shock re-acceleration of pre-existing seed relativistic electrons. We suggest that some of the seed relativistic electrons originate from late-type, star-forming galaxies in this region.

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Chong Ge, Ming Sun, Ruo-Yu Liu, Lawrence Rudnick, Craig Sarazin, William Forman, Christine Jones, Hao Chen, Wenhao Liu, Masafumi Yagi, Alessandro Boselli, Matteo Fossati, Giuseppe Gavazzi. 2019-04-18. A merger shock in Abell 1367. https://doi.org/10.1093/mnrasl%2Fslz049

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