What fraction of the density fluctuations in the Perseus cluster core is due to gas sloshing rather than AGN feedback?

TL;DR

This study investigates the origins of density fluctuations in the Perseus cluster core, finding that gas sloshing likely accounts for most fluctuations beyond 60kpc, challenging the role of AGN feedback in those regions.

Contribution

The paper introduces a method using mock Chandra observations to differentiate between density fluctuations caused by gas sloshing and AGN feedback in galaxy cluster cores.

Findings

Density fluctuations beyond 60kpc are consistent with gas sloshing alone.

AGN feedback may be insufficient to counter cooling outside 60kpc.

Gas sloshing significantly influences cluster core structure beyond central regions.

Abstract

Deep Chandra observations of the core of the Perseus cluster show a plethora of complex structure. It has been found that when the observed density fluctuations in the intracluster medium are converted into constraints on AGN induced turbulence, the resulting turbulent heating rates are sufficient to balance cooling locally throughout the central 220kpc. However while the signatures of AGN feedback (inflated bubbles) dominate the central 60kpc in X-ray images, beyond this radius the intracluster medium is increasingly shaped by the effects of gas sloshing, which can also produce subtle variations in X-ray surface brightness. We use mock Chandra observations of gas sloshing simulations to investigate what fraction of the observed density fluctuations in the core of the Perseus galaxy cluster may originate from sloshing rather than AGN induced feedback. Outside 60kpc, we find that the observed level of the density fluctuations is broadly consistent with being produced by sloshing alone. If this is the case, AGN-generated turbulence is likely to be insufficient in combating cooling outside 60kpc.