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arXiv · 1708.00789

Complex diffuse emission in the $z=0.52$ cluster PLCK~G004.5-19.5

J. G. Albert·C. Sifón·A. Stroe·F. Mernier·H. T. Intema·H. J. A. Röttgering·G. Brunetti
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Abstract

We present radio observations of the galaxy cluster PLCK G004.5-19.5 ($z=0.52$) using the Giant Metrewave Radio Telescope at 150~MHz, 325~MHz, and 610~MHz. We find an unusual arrangement of diffuse radio emission in the center and periphery of the cluster, as well as several radio galaxies with head-tail emission. A patch of peripheral emission resembles a radio relic, and central emission resembles a radio halo. Reanalysis of archival XMM-Newton X-ray data shows that PLCK G004.5-19.5 is disturbed, which has a known correlation with the existence of radio relics and halos. Given that the number of known radio halos and radio relics at $z>0.5$ is very limited, PLCK G004.5-19.5 is an important addition to understanding merger-related particle acceleration at higher redshifts.

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J. G. Albert, C. Sifón, A. Stroe, F. Mernier, H. T. Intema, H. J. A. Röttgering, G. Brunetti. 2017-08-02. Complex diffuse emission in the $z=0.52$ cluster PLCK~G004.5-19.5. https://doi.org/10.1051/0004-6361%2F201730496

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