Disentangling AGN Feedback and Sloshing in the Perseus Cluster with XRISM: Insights from Simulations

TL;DR

This study uses simulations to disentangle the effects of AGN feedback and sloshing on gas motions in the Perseus cluster, aiding interpretation of XRISM X-ray spectroscopic data.

Contribution

It introduces a systematic simulation approach to distinguish the roles of AGN feedback and sloshing in ICM velocity profiles, matching observations.

Findings

Neither sloshing nor AGN feedback alone reproduces observed velocity dispersions.

Combined effects of sloshing and AGN activity match the observed velocity profiles.

Distinct spatial signatures for sloshing and AGN feedback are identified.

Abstract

High-resolution X-ray spectroscopy with XRISM has revealed complex, non-monotonic velocity dispersion profiles in the Perseus cluster, pointing to a complex interplay between at least two physical drivers of motions caused by dynamical processes within the intracluster medium (ICM). To further explore this conclusion, we perform a suite of idealized, controlled simulations targeting the relative roles of merger-induced sloshing and active galactic nucleus (AGN) feedback. Our models systematically isolate and combine these mechanisms to predict observable velocity profiles and X-ray line shapes, providing direct comparison to XRISM and Hitomi data. We find that neither sloshing nor AGN activity alone can reproduce the observed velocity dispersion profile; only their combined action matches the elevated dispersions both at the cluster core and outskirts. Power-spectrum analysis reveals distinct spatial signatures: sloshing generates large-scale coherent motions, while AGN feedback injects turbulence and broadens the velocity spectrum at small scales, especially in the core. By forward-modeling spectral line profiles, we show how these dynamics imprint unique observational signatures on X-ray emission. Our results underscore the necessity of accounting for both large-scale and small-scale drivers of gas motions in the ICM when interpreting high-resolution spectroscopic data, and provide guidance for the analysis of forthcoming XRISM observations.