KAT-7 observations of a mass-selected sample of galaxy clusters

Abstract

The presence of megaparsec-scale radio halos in galaxy clusters has already been established by many observations over the last two decades. The emerging explanation for the formation of these giant sources of diffuse synchrotron radio emission is that they trace turbulent regions in the intracluster medium, where particles are trapped and accelerated during cluster mergers. Our current observational knowledge is, however, mainly limited to massive systems. Here we present observations of a sample of 14 mass-selected galaxy clusters, i.e. $M_{500}>4\times 10^{14}$~M${}_{\odot }$, in the Southern Hemisphere, aimed to study the occurrence of radio halos in low mass clusters and test the correlation between the radio halo power at 1.4 GHz $P_{1.4}$ and the cluster mass $M_{500}$. Our observations were performed with the 7-element Karoo Array Telescope at 1.86 GHz. We found three candidates to host diffuse cluster-scale emission and derived upper limits at the level of $0.6-1.9\times 10^{24}$~Watt~Hz${}^{-1}$ for $\sim 50\%$ of the clusters in the sample, significantly increasing the number of clusters with radio halo information in the considered mass range. Our results confirm that bright radio halos in less massive galaxy clusters are statistically rare.

14 pages, 12 (low resolution) figures, MNRAS accepted

References in corpus (9)

• On the connection between giant radio halos and cluster mergers
• GMRT Radio Halo Survey in galaxy clusters at z = 0.2 -- 0.4. II.The eBCS clusters and analysis of the complete sample
• GMRT Radio Halo Survey in galaxy clusters at z = 0.2 -- 0.4 I.The REFLEX sub--sample
• Cosmic rays and Radio Halos in galaxy clusters : new constraints from radio observations
• New scaling relations in cluster radio halos and the re-acceleration model
• On the occurrence of Radio Halos in galaxy clusters - Insight from a mass-selected sample
• The Extended GMRT Radio Halo Survey II: Further results and analysis of the full sample
• Radio observations of the Horologium-Reticulum Supercluster -I. A3158: Excess star-forming galaxies in a merging cluster?
• ATCA observations of the galaxy cluster Abell 3921 - I. Radio emission from the central merging sub-clusters

Cited by in corpus (21)

• Hydrogen Epoch of Reionization Array (HERA)
• Diffuse Radio Emission from Galaxy Clusters
• The MeerKAT Galaxy Cluster Legacy Survey I. Survey Overview and Highlights
• Shocks and cold fronts in merging and massive galaxy clusters: new detections with Chandra
• The two-component giant radio halo in the galaxy cluster Abell 2142
• Radio fossils, relics, and haloes in Abell 3266: cluster archaeology with ASKAP-EMU and the ATCA
• Can giant radio halos probe the merging rate of galaxy clusters?
• Evolutionary phases of merging clusters as seen by LOFAR
• Diffuse galaxy cluster emission at 168 MHz within the Murchison Widefield Array Epoch of Reionization 0-hour field
• MERGHERS Pilot: MeerKAT discovery of diffuse emission in nine massive Sunyaev-Zel'dovich-selected galaxy clusters from ACT
• A Massive Cluster at z = 0.288 Caught in the Process of Formation: The Case of Abell 959
• Discovery of a radio halo (and relic) in a $M_{500}<2\times 10^{14}$ M${}_{\odot }$ cluster
• The merging galaxy cluster Abell 3266 at low radio frequencies
• Low-frequency radio study of MACS clusters at 610 and 235 MHz using the GMRT
• Diffuse radio emission from non-Planck galaxy clusters in the LoTSS-DR2 fields
• Dynamics of Abell 3266 - I. An Optical View of a Complex Merging Cluster
• LOFAR Detection of a Low-Power Radio Halo in the Galaxy Cluster Abell 990
• uGMRT detection of cluster radio emission in low-mass Planck~SZ clusters
• Abell 0399-Abell 0401 radio bridge spectral index: the first multifrequency detection
• Radio multifrequency observations of galaxy clusters. The Abell 399$-$401 pair
• Low-frequency integrated radio spectra of diffuse, steep-spectrum sources in galaxy clusters: palaeontology with the MWA and ASKAP