Evidence of sloshing-driven mini-halo formation in the cool-core cluster RXCJ1558.3-1410

TL;DR

This study investigates the connection between X-ray and radio emissions in the cool-core galaxy cluster RXCJ1558.3-1410, revealing that gas sloshing, rather than AGN activity, likely powers its radio mini-halo.

Contribution

It provides multiwavelength evidence linking gas sloshing to mini-halo formation, highlighting the role of ICM dynamics over AGN feedback.

Findings

Detection of new X-ray cavity indicating AGN mechanical power.

Identification of a cold front caused by gas sloshing.

Spatial correlation between mini-halo and X-ray features.

Abstract

Radio mini-halos are perplexing features, typically hosted by X-ray cool-core galaxy clusters. Understanding the connection between thermal X-ray and non-thermal radio emission is key to uncovering their origin. Here, we present a multiwavelength study of the cool-core cluster RXCJ1558.3-1410 using archival Chandra X-ray and wideband uGMRT radio data (Bands 3, 4 and 5). Our improved analysis confirms a previously known X-ray cavity at $\sim$36 kpc south-east of the cluster centre and we report a new cavity at $\sim$42 kpc to the north-west. These cavities suggest that the AGN provides mechanical power of $\sim$$6.0 \times 10^{44}$ erg s$^{-1}$, sufficient to offset radiative cooling in the ICM. We also detect a sharp surface brightness edge at $\sim$72 kpc south-east of the centre, characterised by a temperature jump and pressure continuity, consistent with a cold front, likely caused by gas sloshing from a minor merger. Our uGMRT images reveals an interesting diffuse emission surrounding the brightest cluster galaxy (BCG), with its edge spatially coinciding with the sloshing cold front and roughly with the cooling radius. Furthermore, a low star formation rate and uniform metal abundance up to the sloshing edge are consistent with the earlier findings of suppression of star formation and metallicity homogenisation by mixing core gas through sloshing. Finally, the spatial correlation between the mini-halo and the observed X-ray features indicates that ICM sloshing, rather than AGN feedback, plays a dominant role in powering the proposed radio mini-halo emission.