A Newly-Discovered Radio Halo in Merging Cluster MACS J2243.3-0935

TL;DR

This paper reports the discovery of a radio halo and a relic candidate in the merging galaxy cluster MACS J2243.3-0935, providing insights into cluster magnetic fields and the origins of relic emissions.

Contribution

It presents the first detection of a radio halo and a relic candidate in this specific merging cluster, with detailed measurements and analysis of their properties.

Findings

Radio halo size approximately 0.9 Mpc

Magnetic field estimated around 1 microGauss

Relic candidate consistent with an infall relic

Abstract

We report the discovery of a radio halo in the massive merging cluster MACSJ2243.3-0935, as well as a new radio relic candidate, using the Giant Meterwave Radio Telescope and the KAT-7 telescope. The radio halo is coincident with the cluster X-ray emission and has a largest linear scale of approximately 0.9 Mpc. We measure a flux density of $10.0\pm 2.0$ mJy at 610 MHz for the radio halo. We discuss equipartition estimates of the cluster magnetic field and constrain the value to be of the order of 1 $\mu$G. The relic candidate is detected at the cluster virial radius where a filament meets the cluster. The relic candidate has a flux density of $5.2\pm 0.8$ mJy at 610 MHz. We discuss possible origins of the relic candidate emission and conclude that the candidate is consistent with an infall relic.