Related papers: Multiple shock structures in a radio selected clus…
Mega-parsec scale radio sources in the form of halos and relics are often detected in dynamically disturbed galaxy clusters. Although they are associated with merger-induced turbulence and shocks, respectively, their formation is not fully…
We present an analysis of archival Chandra data of the merging galaxy cluster ClG 0217+70. The Fe XXV He$\alpha$ X-ray emission line is clearly visible in the 25 ks observation, allowing a precise determination of the redshift of the…
We present evidence for the existence of shock waves caused by the formation of the large-scale structure. In some clusters of galaxies peripherally located sources of extended diffuse radio emission exist, the so-called cluster radio…
In some clusters of galaxies, a diffuse non-thermal emission is present, not obviously associated with any individual galaxy. These sources have been identified as relics, mini-halos, and halos according to their properties and position…
New images of 7 radio halos and relics, obtained with the Very Large Array at 20 or 90 cm, are presented here. The existence of a cluster-wide radio halo in the clusters A 665 and CL 0016+16 is confirmed. Both these clusters share the…
Radio relics are diffuse radio sources observed in galaxy clusters, probably produced by shock acceleration during cluster-cluster mergers. Their large size, of the order of 1 Mpc, indicates that the emitting electrons need to be…
Radio halos and relics are diffuse radio sources found in galaxy clusters showing significant substructure at X-ray wavelengths. These sources provide important information about non-thermal processes taking place in the ICM. Until now only…
Radio halos and radio relics are diffuse synchrotron sources that extend over Mpc-scales and are found in a number of merger galaxy clusters. They are believed to form as a consequence of the energy that is dissipated by turbulence and…
Mergers of galaxy clusters are the most energetic events in the universe, driving shock and cold fronts, generating turbulence, and accelerating particles that create radio halos and relics. The galaxy cluster CL 0217+70 is a remarkable…
Hierarchical models of structure formation predict that galaxy clusters grow via mergers of smaller clusters and galaxy groups, as well as through continuous accretion of gas. MACS J0717.5+3745 is an X-ray luminous and complex merging…
A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo Survey…
Some merging galaxy clusters host diffuse elongated radio sources, also called radio relics. It is proposed that these radio relics trace shock waves in the intracluster medium created during a cluster merger event. Within the shock waves…
Deep X-ray data from CHANDRA and XMM-Newton, and GMRT radio data are presented for ZwCl 2341.1+0000, an extremely unusual and complex merging cluster of galaxies at the intersection of optical filaments. We propose that energetics of…
We investigate binary mergers of galaxy clusters, the formation of shocks, and the resulting radio relics using three-dimensional simulations. The initial setup consists of two idealized spherical subclusters with a mass ratio below three,…
We have performed 323 MHz observations with the Giant Metrewave Radio Telescope of the most promising candidates selected from the MACS catalog. The aim of the work is to extend our knowledge of the radio halo and relic populations to…
We present new, high frequency radio observations of the merging galaxy clusters PLCK G287.0+32.9, Abell 2744, and Bullet. These clusters are known to host $\sim$Mpc scale sources, known as radio halos, which are formed by the acceleration…
We present a combined radio, X-ray and optical study of the galaxy cluster RXCJ2003.5-2323. The cluster hosts one of the largest, most powerful and distant giant radio halos known to date, suggesting that it may be undergoing a strong…
Pairs of radio relics are believed to form during cluster mergers, and are best observed when the merger occurs in the plane of the sky. Mergers can also produce radio halos, through complex processes likely linked to turbulent…
Some merging galaxy clusters host diffuse extended radio emission, so-called radio halos and relics. Here we present observations between 147 MHz and 4.9 GHz of a new radio-selected galaxy cluster 1RXS J0603.3+4214 (z=0.225). The cluster is…
Radio halos are synchrotron radio sources detected in some massive galaxy clusters. Their Mpc-size indicates that (re)acceleration processes are taking place in the host cluster. X-ray catalogues of galaxy clusters have been used in the…