Related papers: Discovering the most elusive radio relic in the sk…
Radio relics are giant sources of diffuse synchrotron radio emission in the outskirts of galaxy clusters that are associated with shocks in the intracluster medium. Still, the origin of relativistic particles that make up relics is not…
We report the discovery of a radio relic in the northeastern periphery of the cluster Abell 2108 (A2108). A2108 is a part of the uGMRT LOw-MAss Galaxy Cluster Survey (GLOMACS), where our main aim is to search for diffuse radio emission…
We observed the cluster CIZA J2242.8+5301 with the Arcminute Microkelvin Imager at $16$ GHz and present the first high radio-frequency detection of diffuse, non-thermal cluster emission. This cluster hosts a variety of bright, extended,…
Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms…
Galaxy clusters undergo mergers that can generate extended radio sources called radio relics. Radio relics are the consequence of merger-induced shocks that propagate in the intra cluster medium (ICM). In this paper we analyse the radio,…
Radio relics in galaxy clusters are thought to be associated with powerful shock waves that accelerate particles via diffusive shock acceleration (DSA). Among the particles accelerated by DSA, relativistic protons should outnumber electrons…
Although radio relics are understood to originate in intracluster shock waves resulting from merger shocks, the most widely used model for describing this (re-)acceleration process at shock fronts, the diffusive shock acceleration (DSA)…
Diffuse radio sources known as radio relics are direct tracers of shocks in the outskirts of merging galaxy clusters. PSZ2 G200.95-28.16, a low-mass merging cluster($\textrm{M}_{500} = (2.7 \pm 0.2) \times 10^{14}~\mathrm{M}_{\odot}$)…
Extended, steep-spectrum radio synchrotron sources are pre-dominantly found in massive galaxy clusters as opposed to groups. LOFAR Two-Metre Sky Survey images have revealed a diffuse, ultra-steep spectrum radio source in the low-mass…
The galaxy cluster CIZA J2242.8+5301 is a well-studied merging galaxy cluster that hosts prominent double radio relics including the famous sausage relic, as well as other diffuse radio sources. Observations at frequencies below 100 MHz are…
We report a discovery of a 1.3 Mpc diffuse radio source with extremely steep spectrum fading radio structures in the vicinity of the Abell 449 cluster of galaxies. Its extended diffuse lobes are bright only at low radio frequencies and…
We present new low-frequency ($\nu = 88$-216 MHz) observations of the complex merging galaxy cluster Abell 3266. These new observations are taken with the Murchison Widefield Array (MWA) in its Phase II 'extended', long-baseline…
Many bright radio relics in the outskirts of galaxy clusters have low inferred Mach numbers, defying expectations from shock acceleration theory and heliospheric observations that the injection efficiency of relativistic particles plummets…
In this paper we address the question why cluster radio relics that are connected to shock acceleration, so-called radio gischt, have preferentially been found in the outskirts of galaxy clusters. By identifying merger shock waves in…
Collisions of galaxy clusters generate shocks and turbulence in the intra-cluster medium (ICM). The presence of relativistic particles and magnetic fields is inferred through the detection of extended synchrotron radio sources such as…
The mega-parsec scale radio relics at the galaxy cluster periphery are intriguing structures. While textbook examples of relics posit arc-like elongated structures at the clusters' peripheries, several relics display more complex structures…
On the largest scales, the Universe consists of voids and filaments making up the cosmic web. Galaxy clusters are located at the knots in this web, at the intersection of filaments. Clusters grow through accretion from these large-scale…
Radio relics are diffuse, extended synchrotron sources that originate from shock fronts generated during cluster mergers. The massive merging galaxy cluster MACS J0717.5+3745 hosts one of the more complex relics known to date. We present…
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…
Radio relics are patches of diffuse synchrotron radio emission that trace shock waves. Relics are thought to form when intra-cluster medium electrons are accelerated by cluster merger induced shock waves through the diffusive shock…