Radio galaxy feedback in X-ray selected groups from COSMOS: the effect on the ICM

TL;DR

This study assesses how radio galaxy feedback influences the intra-group medium in galaxy groups, showing that radio-AGN can unbind gas in less massive groups but not in larger clusters, affecting their entropy-temperature relation.

Contribution

It quantifies the mechanical energy from radio-AGN in galaxy groups and demonstrates its role in breaking self-similarity in entropy-temperature scaling.

Findings

Radio-AGN can unbind a significant fraction of intra-group gas.

The energy output is insufficient to unbind gas in massive clusters.

Results match observed entropy-temperature relation break in galaxy groups.

Abstract

We quantify the importance of the mechanical energy released by radio-galaxies inside galaxy groups. We use scaling relations to estimate the mechanical energy released by 16 radio-AGN located inside X-ray detected galaxy groups in the COSMOS field. By comparing this energy output to the host groups' gravitational binding energy, we find that radio galaxies produce sufficient energy to unbind a significant fraction of the intra-group medium. This unbinding effect is negligible in massive galaxy clusters with deeper potential wells. Our results correctly reproduce the breaking of self-similarity observed in the scaling relation between entropy and temperature for galaxy groups.