# AGN jet feedback on a moving mesh: cocoon inflation, gas flows and turbulence

## TL;DR

This paper introduces a new jet feedback scheme in the moving mesh code Arepo, demonstrating how AGN jets influence the intracluster medium by inflating cavities, driving turbulence, and offsetting cooling, with results aligning with observations of galaxy clusters.

## Contribution

The paper develops and validates a novel jet feedback implementation in Arepo, comparing injection techniques and analyzing jet effects on the ICM, including turbulence and heating mechanisms.

## Key findings

- Jets significantly affect the ICM and offset overcooling.
- Jet-driven turbulence is a minor heating source.
- Combined effects produce velocities consistent with observations.

## Abstract

In many observed galaxy clusters, jets launched by the accretion process on to supermassive black holes, inflate large-scale cavities filled with energetic, relativistic plasma. This process is thought to be responsible for regulating cooling losses, thus moderating the inflow of gas on to the central galaxy, quenching further star formation and maintaining the galaxy in a red and dead state. In this paper, we implement a new jet feedback scheme into the moving mesh-code arepo, contrast different jet injection techniques and demonstrate the validity of our implementation by comparing against simple analytical models. We find that jets can significantly affect the intracluster medium (ICM), offset the overcooling through a number of heating mechanisms, as well as drive turbulence, albeit within the jet lobes only. Jet-driven turbulence is, however, a largely ineffective heating source and is unlikely to dominate the ICM heating budget even if the jet lobes efficiently fill the cooling region, as it contains at most only a few per cent of the total injected energy. We instead show that the ICM gas motions, generated by orbiting substructures, while inefficient at heating the ICM, drive large-scale turbulence and when combined with jet feedback, result in line-of-sight velocities and velocity dispersions consistent with the Hitomi observations of the Perseus cluster.