Related papers: Radio and X-ray Shocks in Clusters of galaxies
Weak shocks in the intracluster medium may accelerate cosmic-ray protons and cosmic-ray electrons differently depending on the angle between the upstream magnetic field and the shock normal. In this work, we investigate how shock obliquity…
In a growing number of galaxy clusters diffuse extended radio sources have been found. These sources are not directly associated with individual cluster galaxies. The radio emission reveal the presence of cosmic rays and magnetic fields in…
We discuss a new technique to constrain models for the origin of radio relics in galaxy clusters using the correlation between the shock Mach number and the radio power of relics. This analysis is carried out using a sample of relics with…
In this paper we review the observational results on Relic radio sources in clusters of galaxies. We discuss their observational properties, structures and radio spectra. We will show that Relics can be divided according to their size,…
Radio relics in galaxy clusters are extended synchrotron sources produced by cosmic-ray electrons in the $\mu$G magnetic field. Many relics are found in the cluster periphery and have a cluster-centric, narrow arc-like shape, which suggests…
Context: Diffuse radio emission, in the form of radio halos and relics, traces regions in clusters with shocks or turbulence, probably produced by cluster mergers. Some models of diffuse radio emission in clusters indicate that virtually…
Some galaxy clusters show diffuse radio emission in the form of peripheral relics (so far attributed to primary, shock-(re)accelerated electrons) or central halos. Analysing radio and X-ray data from the literature, we find new connections…
Non-thermal emission from relativistic electrons gives insight into the strength and morphology of intra-cluster magnetic fields, as well as providing powerful tracers of structure formation shocks. Emission caused by Cosmic Ray (CR)…
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…
In several merging clusters of galaxies so-called cluster radio relics have been observed. These are extended radio sources which do not seem to be associated with any radio galaxy. Two competing physical mechanisms to accelerate the radio…
It is generally accepted that radio relics are the result of synchrotron emission from shock-accelerated electrons. Current models, however, are still unable to explain several aspects of their formation. In this paper, we focus on three…
Radio relics are diffuse synchrotron sources in the outskirts of merging galaxy clusters energized by the merger shocks. In this paper, we present an overview of the radio relics in massive cluster mergers identified in the new TNG-Cluster…
In order to understand certain observed features of arc-like giant radio relics such as the rareness, uniform surface brightness, and curved integrated spectra, we explore a diffusive shock acceleration (DSA) model for radio relics in which…
An important aspect of the radio emission from galaxy clusters is represented by the diffuse radio sources associated with the intracluster medium: radio halos, relics and mini-halos. The radio halos and relics are indicators of cluster…
Galaxy clusters grow by mergers with other clusters and galaxy groups. These mergers create shocks within the intracluster medium (ICM). It is proposed that within the shocks particles can be accelerated to extreme energies. In the presence…
The diffusive shock acceleration scenario is usually invoked to explain radio relics, although the detailed driving mechanism is still a matter of debate. Our aim is to constrain models for the origin of radio relics by comparing observed…
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,…
A joint hadronic model is shown to quantitatively explain the observations of diffuse radio emission from galaxy clusters in the form of minihalos, giant halos, relics, and their hybrid, transitional stages. Cosmic-ray diffusion of order…
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…
Diffuse radio sources in galaxy clusters are unique signposts of cluster assembly in the Universe. Our knowledge of their observational properties has considerably improved over the past decade, and the long standing questions concerning…