Related papers: Non-thermal phenomena in galaxies clusters
We submit that non thermalized support for the outer intracluster medium in relaxed galaxy clusters is provided by turbulence, driven by inflows of intergalactic gas across the virial accretion shocks. We expect this component to increase…
Non-thermal components are key ingredients for understanding clusters of galaxies. In the hierarchical model of structure formation, shocks and large-scale turbulence are unavoidable in the cluster formation processes. Understanding the…
Among the models proposed to account for the new component of diffuse EUV and soft X-ray emission from clusters of galaxies (first discovered in Virgo) are two key contestants: the non-thermal scenario which postulates a population of…
X-ray observations of galaxy cluster merger shocks can be used to constrain nonthermal processes in the intracluster medium (ICM). The presence of nonthermal pressure components in the ICM, as well as the shock acceleration of particles and…
We calculate the distribution of electrons in clusters of galaxies, resulting from thermalization processes in the presence of stochastic acceleration due to plasma waves. We show that the electron distribution can deviate from a…
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…
Cluster mergers drive shocks into the intracluster medium which heat and compress the thermal gas. X-ray observations of shocks can be used to determine the geometry and kinematics of the merger. Merger shocks should also accelerate…
A numerical simulation model of the injection and cooling of nonthermal particles energized by shocks formed in merging clusters of galaxies is used to fit radio and X-ray data observed from the Coma cluster of galaxies. The results are…
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…
We analyse new results of Chandra and Suzaku which found a flux of hard X-ray emission from the compact region around Sgr A$^\ast$ (r ~ 100 pc). We suppose that this emission is generated by accretion processes onto the central supermassive…
In the next years the FERMI gamma ray telescope and the Cherenkov telescopes will put very stringent constraints to models of gamma ray emission from galaxy clusters providing crucial information on relativistic particles in the…
We have developed a numerical model for the temporal evolution of particle and photon spectra resulting from nonthermal processes at the shock fronts formed in merging clusters of galaxies. Fermi acceleration is approximated by injecting…
The detailed velocity structure of the diffuse X-ray emitting intra-cluster medium (ICM) remains one of the last missing key ingredients in understanding the microphysical properties of these hot baryons and constraining our models of the…
Radio emission in the direction of galaxy clusters is due to the individual emission of AGNs, and to the diffuse non-thermal emission of the intracluster medium (ICM). The population of AGNs in clusters is correlated to the overall halo…
We have developed a numerical model for the temporal evolution of particle and photon spectra resulting from nonthermal processes at the shock fronts formed in merging clusters of galaxies. Fermi acceleration is approximated by injecting…
The relevance of non-thermal cluster studies and the importance of combining observations of future radio surveys with WFXT data are discussed in this paper.
Recent statistical X-ray measurements of the intracluster medium (ICM) indicate that gas temperature profiles in the outskirts of galaxy clusters deviate from self-similar evolution. Using a mass-limited sample of galaxy clusters from…
Galaxy cluster merger shocks are the main agent for the thermalization of the intracluster medium and the energization of cosmic ray particles in it. Shock propagation changes the state of the tenuous intracluster plasma, and the…
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…
Thermal radio and X-ray emission has been traditionally associated with the formation of stars. However, in recent years, non-thermal radiation from massive star forming regions has been detected. Synchrotron radio emission and non-thermal…