Related papers: Shock acceleration as origin of the radio relic in…

New observations of Sgr A have been carried out with the VLA using the broadband (2 GHz) continuum mode at 5.5 GHz, covering the central 30 pc region of the RBZ at the Galactic center. Using the MS-MFS algorithms in CASA, we have imaged Sgr…

We present high-sensitivity follow-up observations of the giant fossil radio lobe in the Ophiuchus galaxy cluster with the upgraded Giant Metrewave Radio Telescope (uGMRT) in the 125-250 MHz and 300-500 MHz frequency bands. The new data…

We report extensive VLA and ATCA observations of the two diffuse radio sources in the cluster of galaxies Abell 548b, which confirm their classification as relics. The two relics (named A and B) show similar flux density, extent, shape,…

Although many of the observed properties of giant radio relics detected in the outskirts of galaxy clusters can be explained by relativistic electrons accelerated at merger-driven shocks, significant puzzles remain. In the case of the…

Radio Relics are typically found to be arc-like regions of synchrotron emission in the outskirts of merging galaxy clusters, bowing out from the cluster center. In most cases they show synchrotron spectra that steepen towards the cluster…

Extended steep-spectrum radio emission in a galaxy cluster is usually associated with a recent merger. However, given the complex scenario of galaxy cluster mergers, many of the discovered sources hardly fit into the strict boundaries of a…

High-resolution radio observations of cluster radio relics often show complex spatial and spectral features. However, it is not clear what these features reveal about the underlying magnetic field properties. We performed three-dimensional…

We present the first multi-frequency analysis of the candidate ultra-steep spectrum radio halo in the galaxy cluster PLCKESZ G171.94$-$40.65, using the upgraded Giant Metrewave Radio telescope (uGMRT; 400 MHz), and Karl G. Jansky Very Large…

We present the results of deep Chandra and XMM-Newton observations of a complex merging galaxy cluster Abell 2256 (A2256) that hosts a spectacular radio relic (RR). The temperature and metallicity maps show clear evidence of a merger…

Cosmological shocks are a critical part of large-scale structure formation, and are responsible for heating the intracluster medium in galaxy clusters. In addition, they are also capable of accelerating non-thermal electrons and protons. In…

Galaxy cluster peripheries provide important information on the nature of ICM/IGM linkage. In this paper we consider potential future observations in the gamma-ray domain at cluster edges involving the radio relic phenomenon. We focus on…

Diffuse radio emission in the form of radio halos and relics has been found in a number of merging galaxy clusters. These structures indicate that shock and turbulence associated with the merger accelerate electrons to relativistic…

Signatures of the re-occurrence of activity in radio-loud AGNs, indicated either by the so-called double-double or X-shaped structures, have been observed in a number of radio sources. All such objects known to date have linear sizes of the…

Galaxy clusters have been found to host a range of diffuse, non-thermal emission components, generally with steep, power law spectra. In this work we report on the detection and follow-up of radio halos, relics, remnant radio galaxies, and…

We observed the rapid radio brightening of GRB 210702A with the Australian Telescope Compact Array (ATCA) just 11hr post-burst, tracking early-time radio variability over a 5hr period on ~15min timescales at 9.0, 16.7, and 21.2GHz. A broken…

We present the analysis of our 13 and 22 cm ATCA observations of the central region of the merging galaxy cluster A3921 (z=0.094). We investigated the effects of the major merger between two sub-clusters on the star formation (SF) and radio…

The aim of this work is to analyse the radio properties of the massive and dynamical disturbed clusters Abell 1451 and Zwcl 0634.1+4750, especially focusing on the possible presence of diffuse emission. We present new GMRT 320 MHz and JVLA…

Spectral index images can be used to constraint the energy spectrum of relativistic electrons and magnetic field distribution in radio halos and relics, providing useful information to understand their formation, evolution and connection to…

We present new results on the shock around the southwest radio lobe of Centaurus A using data from the Chandra Very Large Programme observations. The X-ray spectrum of the emission around the outer southwestern edge of the lobe is well…

We present a multiwavelength analysis of the galaxy cluster Abell 795 (z=0.1374), known for its extended (200 kpc) radio emission with a steep spectral index of unclear origin surrounding the brightest cluster galaxy (BCG), and for sloshing…