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

TL;DR

This paper reports the discovery of a giant radio halo in the merging galaxy cluster Abell 1351, supporting the link between cluster mergers and diffuse radio emission due to turbulence-driven particle re-acceleration.

Contribution

First detection of a giant radio halo in Abell 1351, linking merger activity with diffuse radio emission in a massive galaxy cluster.

Findings

Radio halo is associated with the most massive substructure.

Cluster's position in the P$_{1.4 GHz}$ - L$_{X}$ plane aligns with other known radio-halo clusters.

Supports turbulence re-acceleration as the origin of diffuse radio emission.

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.