Sloshing Gas in the Core of the Most Luminous Galaxy Cluster RXJ1347.5-1145

TL;DR

This paper investigates the merger history of the luminous galaxy cluster RXJ1347.5-1145 using multiwavelength data, revealing core gas sloshing caused by past gravitational interactions with a secondary subcluster.

Contribution

It provides new constraints on the cluster's merger history by linking core gas sloshing to multiple past gravitational interactions, supported by multiwavelength observations.

Findings

Core gas is undergoing sloshing due to a past gravitational perturbation.

The secondary subcluster previously passed by the primary cluster over 0.6 Gyr ago.

The subcluster's gas has been stripped during its current crossing.

Abstract

We present new constraints on the merger history of the most X-ray luminous cluster of galaxies, RXJ1347.5-1145, based its unique multiwavelength morphology. Our X-ray analysis confirms the core gas is undergoing "sloshing" resulting from a prior, large scale, gravitational perturbation. In combination with extensive multiwavelength observations, the sloshing gas points to the primary and secondary clusters having had at least two prior strong gravitational interactions. The evidence supports a model in which the secondary subcluster with mass M=4.8$\pm2.4 \times$ 10$^{14}$ M$_{\odot}$ has previously ($\gtrsim$0.6 Gyr ago) passed by the primary cluster, and has now returned for a subsequent crossing where the subcluster's gas has been completely stripped from its dark matter halo. RXJ1347 is a prime example of how core gas sloshing may be used to constrain the merger histories of galaxy clusters through multiwavelength analyses.