Cosmological Simulation of Galaxy Groups and Clusters-I: Global Effect of Feedback from Active Galactic Nuclei

Abstract: In this study we quantify the properties of the gas and dark matter around active galactic nuclei (AGN) in simulated galaxy groups and clusters and analyze the effect of AGN feedback on the surrounding intra-cluster (group) medium. Our results suggest downsizing of AGN luminosity with host halo mass, supporting the results obtained from clustering studies of AGN. By examining the temperature and density distribution of the gas in the vicinity of AGN we show that due to feedback from the central engine, the gas gets displaced from the centre of the group/cluster resulting in a reduction of the density but an enhancement of temperature. We show that these effects are pronounced at both high and low redshifts and propose new observables to study the effect of feedback in higher redshift galaxies. We also show that the average stellar mass is decreased in halos in the presence of AGN feedback confirming claims from previous studies. Our work for the first time uses a fully cosmological-hydrodynamic simulation to evaluate the global effects of AGN feedback on their host dark matter halos as well as galaxies at scales of galaxy groups and clusters.