Mergers, relics and magnetic fields: The complex case of A2256

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Abstract
Clusters of galaxies undergo multiple mergers during their lifetimes. Each merger drives shocks into the intracluster medium (ICM) which can heat the thermal gas, accelerate relativistic particles, and compress magnetic fields. Radio observations toward a number of clusters reveal large regions of diffuse synchrotron emission (halos and relics) which are not associated with individual host galaxies but are general properties of the ICM. Clusters host to this diffuse emission reveal significant evidence of recent or on‐going merger activity. We present deep VLA observations of the diffuse radio halo and relic emission in Abell 2256. Our new observations provide the first detailed image of the central diffuse radio halo emission in this cluster. The high fractional polarization of the relic allow us to use Faraday rotation measure observations to place constraints on the merger geometry of the system. In addition, the relic is composed of a number of synchrotron filaments which suggest the presence of spatially intermittent magnetic fields in this cluster.