Multiphase Signatures of AGN Feedback in Abell 2597

TL;DR

This study uses Chandra X-ray and VLA radio data to analyze multiphase gas, cavities, and hot gas structures in Abell 2597's core, providing insights into AGN feedback mechanisms and their role in quenching cooling flows.

Contribution

It presents the first observational evidence supporting cavity-driven AGN heating models through detailed spectral maps and multiwavelength analysis of Abell 2597.

Findings

Detection of a kpc-scale X-ray cavity network.

Identification of a 15 kpc filament of multiphase gas.

Observation of a hot gas arc bordering a cavity, consistent with AGN heating models.

Abstract

We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool core cluster Abell 2597. The data reveal an extensive kpc-scale X-ray cavity network as well as a 15 kpc filament of soft-excess gas exhibiting strong spatial correlation with archival VLA radio data. In addition to several possible scenarios, multiwavelength evidence may suggest that the filament is associated with multiphase (10^3 - 10^7 K) gas that has been entrained and dredged-up by the propagating radio source. Stemming from a full spectral analysis, we also present profiles and 2D spectral maps of modeled X-ray temperature, entropy, pressure, and metal abundance. The maps reveal an arc of hot gas which in projection borders the inner edge of a large X-ray cavity. Although limited by strong caveats, we suggest that the hot arc may be (a) due to a compressed rim of cold gas pushed outward by the radio bubble or (b) morphologically and energetically consistent with cavity-driven active galactic nucleus (AGN) heating models invoked to quench cooling flows, in which the enthalpy of a buoyant X-ray cavity is locally thermalized as ambient gas rushes to refill its wake. If confirmed, this would be the first observational evidence for this model.