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arXiv · 0909.0437

A giant radio halo in the massive and merging cluster Abell 1351

S. Giacintucci·T. Venturi·R. Cassano·D. Dallacasa·G. Brunetti
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Abstract

We report on the detection of diffuse radio emission in the X-ray luminous and massive galaxy cluster A1351 (z=0.322) using archival Very Large Array data at 1.4 GHz. Given its central location, morphology, and Mpc-scale extent, we classify the diffuse source as a giant radio halo. X-ray and weak lensing studies show A1351 to be a system undergoing a major merger. The halo is associated with the most massive substructure. The presence of this source is explained assuming that merger-driven turbulence may re-accelerate high-energy particles in the intracluster medium and generate diffuse radio emission on the cluster scale. The position of A1351 in the logP$_{1.4 GHz}$ - logL$_{X}$ plane is consistent with that of all other radio-halo clusters known to date, supporting a causal connection between the unrelaxed dynamical state of massive ($>10^{15} M_{\odot}$) clusters and the presence of giant radio halos.

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S. Giacintucci, T. Venturi, R. Cassano, D. Dallacasa, G. Brunetti. 2009-09-02. A giant radio halo in the massive and merging cluster Abell 1351. https://doi.org/10.1088/0004-637x/704/1/l54

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