# Constraining Radio Mode Feedback in Galaxy Clusters with the Cluster Radio AGN Properties to z$\sim$1

## TL;DR

This study analyzes the properties and evolution of radio AGN in galaxy clusters up to redshift 1, revealing their concentration in cluster centers, dependence on cluster mass, and implications for radio mode feedback energy.

## Contribution

It provides the first detailed measurement of the halo occupation number of radio AGN in clusters up to z~1 and explores their evolution and feedback energy contribution.

## Key findings

- Radio AGN are highly concentrated in cluster centers up to z~1.
- Number of radio AGN per cluster scales with cluster mass as N∝M^{1.2±0.1}.
- Radio mode feedback energy correlates with cluster mass and redshift, impacting cluster evolution.

## Abstract

We study the properties of the Sydney University Molonglo Sky Survey (SUMSS) 843~MHz radio AGN population in galaxy clusters from two large catalogs created using the Dark Energy Survey (DES): $\sim$11,800 optically selected RM-Y3 and $\sim$1,000 X-ray selected MARD-Y3 clusters. We show that cluster radio loud AGN are highly concentrated around cluster centers to $z\sim1$. We measure the halo occupation number for cluster radio AGN above a threshold luminosity, finding that the number of radio AGN per cluster increases with cluster halo mass as $N\propto M^{1.2\pm0.1}$ ($N\propto M^{0.68\pm0.34}$) for the RM-Y3 (MARD-Y3) sample. Together, these results indicate that radio mode feedback is favoured in more massive galaxy clusters. Using optical counterparts for these sources, we demonstrate weak redshift evolution in the host broad band colors and the radio luminosity at fixed host galaxy stellar mass. We use the redshift evolution in radio luminosity to break the degeneracy between density and luminosity evolution scenarios in the redshift trend of the radio AGN luminosity function (LF). The LF exhibits a redshift trend of the form $(1+z)^\gamma$ in density and luminosity, respectively, of $\gamma_{\rm D}=3.0\pm0.4$ and $\gamma_{\rm P}=0.21\pm0.15$ in the RM-Y3 sample, and $\gamma_{\rm D}=2.6\pm0.7$ and $\gamma_{\rm P}=0.31\pm0.15$ in MARD-Y3. We discuss the physical drivers of radio mode feedback in cluster AGN, and we use the cluster radio galaxy LF to estimate the average radio-mode feedback energy as a function of cluster mass and redshift and compare it to the core ($<0.1R_{500}$) X-ray radiative losses for clusters at $z<1$.