Abell 2142 at large scales: An extreme case for sloshing?

TL;DR

This study reveals that large-scale sloshing in galaxy clusters extends beyond cores, with a new distant cold front in A2142, suggesting sloshing influences the entire cluster and may trigger large-scale radio emissions.

Contribution

First detection of a distant cold front at about one Mpc in A2142, demonstrating that sloshing affects the entire cluster scale beyond the core region.

Findings

Discovery of a new cold front at ~1 Mpc from the center.

Sloshing extends to nearly half the virial radius.

Large-scale sloshing may trigger Mpc-scale radio emission.

Abstract

We present results obtained with a new XMM-Newton observation of A2142, a famous textbook example of cluster with multiple cold fronts, which has been studied in detail with Chandra but whose large scale properties are presented here for the first time. We report the discovery of a a new cold front, the most distant one ever detected in a galaxy cluster, at about one Mpc from the center to the SE. Residual images, thermodynamics and metal abundance maps are qualitatively in agreement with predictions from numerical simulations of the sloshing phenomenon. However, the scales involved are much larger, similarly to what recently observed in the Perseus cluster. These results show that sloshing is a cluster-wide phenomenon, not confined in the cores, which extends well beyond the cooling region involving a large fraction of the ICM up to almost half of the virial radius. The absence of a cool core and a newly discovered giant radio halo in A2142, in spite of its relaxed X-ray morphology, suggest that large scale sloshing, or the intermediate merger which caused it, may trigger Mpc-scale radio emission and may lead to the disruption of the cluster cool core