Possible Dark Matter annihilation in the galaxy cluster A520

Abstract

Dark Matter annihilation is a possible source of relativistic electrons in galaxy clusters; these electrons, interacting with intra-cluster magnetic fields, can contribute to the diffuse radio emission observed in several clusters. We explore the possibility that Dark Matter annihilation can be at the origin of the radio emission in the cluster A520. We find that, if a radio emission of Dark Matter origin is present in this cluster, it can be observed in a region in the NE part of the cluster, whereas we expect that in most parts of the cluster the emission from ordinary matter should be dominant. High-energy measurements in X-rays and gamma rays don't appear to be suitable to discriminate between ordinary and Dark Matter origin for the models we have considered, because the corresponding non-thermal emissions predicted in this cluster are well below the sensitivity of present and forthcoming instruments.