Related papers: Non-thermal phenomena in galaxy clusters
Observations of galaxy clusters show radio emission extended over almost the system scale, necessitating mechanisms for particle acceleration. Previous models for acceleration such as diffusive shock acceleration and that due to turbulence…
There is a growing evidence that extended radio halos are most likely generated by electrons reaccelerated via some kind of turbulence generated in the cluster volume during major mergers. It is well known that Alfv\'en waves channel most…
We present self-consistent cosmological magnetohydrodynamic (MHD) simulations that simultaneously follow the formation of a galaxy cluster and the magnetic field ejection by an active galactic nucleus (AGN). We find that the magnetic fields…
There is compelling evidence that at least some clusters of galaxies are powerful sources of non-thermal radiation. In all cases where this radiation has been detected, a general trend is that high energy densities of cosmic rays and…
A short review on theoretical implications of non-thermal emission (radio, extreme ultraviolet, high energy X-ray) from the intra-cluster medium is given. The origin of cluster radio halos and cluster radio relics is discussed within the…
Almost two decades of observations of radio emission in galaxy clusters have proven the existence of relativistic particles and magnetic fields that generate extended synchrotron emission in the form of radio halos. In the current scenario,…
Low-frequency radio observations are revealing an increasing number of diffuse synchrotron sources from galaxy clusters, dominantly in the form of radio halos or radio relics. The existence of this diffuse synchrotron emission indicates the…
Clusters of galaxies are sites of acceleration of charged particles and sources of non-thermal radiation. We report on new constraints on the population of cosmic rays in the Intra Cluster Medium (ICM) obtained via radio observations of a…
Cosmological simulations of magnetic fields in galaxy clusters show that remarkable agreement between simulations and observations of Faraday rotation and radio haloes can be achieved assuming that seed fields of 10^{-9} G were present at…
We propose a mechanism for the early generation of the mean Intracluster magnetic field in terms of magnetized galactic winds. These winds are the result of starburst phases of the cluster galaxies, assumed to produce the predominant…
Diffuse, non-thermal extended emission not associated with the AGN phenomenon, found in many clusters of galaxies hosted by an AGN, are related to the acceleration of cosmic rays. In the current work we present preliminary evidence of…
We discuss the diffuse emission of gamma rays and neutrinos from galaxy clusters in the viable models for structure formation in the universe. We use a self-consistent picture for cluster formation and evolution starting from a primordial…
The discovery of diffuse synchrotron radio emission and, more recently, of the hard X-ray (HXR) tails have triggered a growing interest about non-thermal phenomena in galaxy clusters. After a brief review of the most important evidences for…
Galaxy clusters are unique laboratories to investigate turbulent fluid motions and large scale magnetic fields. Synchrotron radio halos at the center of merging galaxy clusters provide the most spectacular and direct evidence of the…
Giant radio halos in galaxy clusters probe mechanisms of particle acceleration connected with cluster merger events. Shocks and turbulence are driven in the inter-galactic-medium (IGM) during clusters mergers and may have a deep impact on…
Simulations of structure formation in the Universe predict accretion shock waves at the boundaries of the large-scale structures as sheets, filaments, and clusters of galaxies. If magnetic fields are present at these shocks, particle…
We search for extended regions of radio emission not associated with Active Galactic Nuclei, known as 'relics', 'halos' and 'mini halo's, in a sample of 70 Abell clusters for which we have radio, optical and X-ray data. AGN can produce…
Recent observations of galaxy clusters in radio and X-ray indicate that cosmic rays and magnetic fields may be energetically important in the intracluster medium. According to the estimates based on theses observational studies, the…
Evidence for nonthermal activity in clusters of galaxies is well established from radio observations of synchrotron emission by relativistic electrons, and new windows (in EUV and Hard X-ray ranges) have provided more powerful tools for its…
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…