Related papers: Observations of extended radio emission in cluster…
Relevant studies of the non-thermal components of the intracluster medium are performed at radio wavelengths. A number of clusters, indeed, exhibits cluster-wide diffuse radio emission, which is indication of the existence of large scale…
A very important aspect of the radio emission from galaxy clusters is represented by the diffuse radio sources associated with the intracluster medium: radio halos and relics. These radio sources indicate the existence of large scale…
The central regions of galaxy clusters are permeated by magnetic fields and filled with relativistic electrons. When clusters merge, the magnetic fields are amplified and relativistic electrons are re-accelerated by turbulence in the intra…
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…
Recent results on the radio emission from galaxy clusters are reviewed, with emphasis both on the radio galaxies and on the diffuse radio emission from the intracluster medium. We show that the formation of the tailed morphology in cluster…
We present a first attempt to investigate the origin of radio-emitting electrons in the newly discovered class of mega radio halos in clusters of galaxies. We study the evolution of relativistic electrons accreted by the external regions of…
Recent observations of high energy (> 20 keV) X-ray emission in a few clusters of galaxies broaden our knowledge of physical phenomena in the intracluster space. This emission is likely to be nonthermal, probably resulting from Compton…
We will discuss the properties and origins of halos and relics including estimates of the cluster magnetic fields, and present results for a few recently discovered halos and relics. The electrons in the suprathermal high energy tail of the…
Recent observations of high energy (> 20 keV) X-ray emission in a few clusters extend and broaden our knowledge of physical phenomena in the intracluster space. This emission is likely to be nonthermal, probably resulting from Compton…
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,…
Radio observations discovered large scale non thermal sources in the central Mpc regions of dynamically disturbed galaxy clusters (radio halos). The morphological and spectral properties of these sources suggest that the emitting electrons…
The most spectacular aspect of cluster radio emission is represented by the large-scale diffuse radio sources, which cannot be obviously associated with any individual galaxy. These sources demonstrate the existence of relativistic…
The Intra-Cluster Medium is characterized by thermal emission, and by the presence of large scale magnetic fields. In some clusters of galaxies a diffuse non-thermal emission is also present, located at the cluster center and named radio…
The existence and extent of non-thermal phenomena in galaxy clusters is now well established. A key question in our understanding of these phenomena is the origin of the relativistic electrons which may be constrained by the modelling of…
Observations with the RXTE and SAX satellites have recently led to the measurement of a second component in the spectra of several clusters of galaxies which are known to have regions of extended radio emission. This new component is quite…
The strong activity of radio galaxies should have led to a nearly ubiquitous presence of fossil radio plasma in the denser regions of the inter-galactic medium as clusters, groups and filaments of galaxies. This fossil radio plasma can…
Low-frequency radio observations of galaxy clusters are the key to detecting the diffuse extended emission associated with them. The presence and properties of such radio sources in galaxy clusters reveal the existence of magnetic fields on…
Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources ("halos" and "relics") related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. I will outline our…
The recent evidences of the presence of magnetic fields and relativistic particles in galaxy clusters are reviewed. The existence of microG-level magnetic fields in cluster atmospheres appears well established from the detection of diffuse…
In the present-day Universe, magnetic fields pervade galaxy clusters, with strengths of a few microGauss obtained from Faraday Rotation. Evidence for cluster magnetic fields is also provided by Megaparsec-scale radio emission, namely radio…