Published May 24, 2024 | Version v1
Journal article

CHEX-MATE: A LOFAR pilot X-ray – radio study on five radio halo clusters

Contributors

Others:

Description

The connection between the thermal and non-thermal properties in galaxy clusters hosting radio halos seems fairly well established. However, a comprehensive analysis of such a connection has only been done for integrated quantities (e.g. L X − P radio relation). In recent years, new-generation radio telescopes have enabled the unprecedented possibility to study the non-thermal properties of galaxy clusters on a spatially resolved basis. In this work, we performed a pilot study to investigate the mentioned properties on five targets by combining X-ray data from the CHEX-MATE project with the second data release from the LOFAR Two meter Sky survey. We find a strong correlation ( r s ∼ 0.7) with a slope less than unity between the radio and X-ray surface brightness. We also report differences in the spatially resolved properties of the radio emission in clusters that show different levels of dynamical disturbance. In particular, less perturbed clusters (according to X-ray parameters) show peaked radio profiles in the centre, with a flattening in the outer regions, while the three dynamically disturbed clusters have steeper profiles in the outer regions. We fitted a model to the radio emission in the context of turbulent re-acceleration with a constant ratio between thermal and non-thermal particles' energy densities and a magnetic field profile linked to the thermal gas density as B ( r ) ∝ n th 0.5 . We found that this simple model cannot reproduce the behaviour of the observed radio emission.

Abstract

International audience

Additional details

Identifiers

URL
https://hal.science/hal-04919205
URN
urn:oai:HAL:hal-04919205v1

Origin repository

Origin repository
UNICA