Abstract Details

Name: Ramij Raja
Affiliation: IIT Indore
Conference ID: ASI2021_342
Title : Origin of diffuse radio emission in the Phoenix and SPT-CL J2031-4037 galaxy cluster
Authors and Co-Authors : Ramij Raja (Department of Astronomy, Astrophysics and Space Engineering, IIT Indore, Simrol, MP-453552, India), Majidul Rahaman (Department of Astronomy, Astrophysics and Space Engineering, IIT Indore, Simrol, MP-453552, India), Abhirup Datta (Department of Astronomy, Astrophysics and Space Engineering, IIT Indore, Simrol, MP-453552, India)
Abstract Type : Poster
Abstract Category : Extragalactic Astronomy
Abstract : Clusters of galaxies are the largest gravitationally bound objects in the present Universe, located at the nodes or the intersections of the filaments of the cosmic web. They form and grow by accreting mass from the filaments via small and large scale mergers. Radio observations of the clusters have revealed the presence of Mpc scale radio emission which are not associated with cluster radio galaxies. These diffuse radio objects provide information about the dynamical state of the clusters, which are important probes to the cluster evolutionary stages, helping us in our understanding of the structure formation processes in the Universe. Here, we present diffuse radio emission from clusters that are either in a relaxed, intermediate and merging state. The Phoenix cluster is a relaxed cool-core cluster that hosts a radio minihalo. We found two cold fronts as well as spiralling cool gas around the cluster center, indicating the presence of gas sloshing. We argue that this sloshing is likely providing the necessary turbulence to reaccelerate in-situ cosmic rays, resulting in the observed radio minihalo. The SPT-CL J2031-4037 is a cluster that is in between merging and relaxed state, hosting a radio halo of the size ~0.7 Mpc. The ICM disturbance in the X-ray image correlates with the radio halo morphology, indicating the possible merger axis. We speculate based on cluster dynamical state and halo spectral index distribution that this radio halo is probably the result of a past less energetic merger event.