Related papers: Non thermal emission in clusters of galaxies
We review the possible mechanisms for production of non-thermal electrons which are responsible for non-thermal radiation in clusters of galaxies. Our primary focus is on non-thermal Bremsstrahlung and inverse Compton scattering, that…
The main goal of this thesis is to study the physical processes that can produce non-thermal emission at high energies in astrophysical objects capable to accelerate particles up to relativistic velocities. In particular, we have studied…
The search for gamma radiation in clusters of galaxies represents a precious tool to investigate the history of these large scale structures. Clusters or sources within them accelerate cosmic rays, as demonstrated by the detection of radio…
The role of X-ray observations for cosmological studies and conclusions is briefly explored. X-rays currently yield cosmologically interesting results on the abundances, evolution and gas content of clusters of galaxies, on the clustering…
Galaxy clusters are known to host a variety of extended radio sources: tailed radio galaxies whose shape is modelled by the interaction with the intra-cluster medium (ICM); radio bubbles filling cavities in the ICM distribution and rising…
Recent multifrequency observations contribute to derive a comprehensive picture of the origin and evolution of relativistic particles in galaxy clusters. In this review I briefly discuss theoretical aspects and open problems of this…
In this paper we study the possibility of probing the low-energy part of the spectrum of non-thermal electrons in galaxy clusters by detecting their non-thermal bremsstrahlung (NTB) emission in the soft gamma ray band, using instruments…
The X-ray emission properties from the hot thermalized plasma that results from the collisions of individual stellar winds and supernovae ejecta within rich and compact star clusters are discussed. We propose a simple analytical way of…
We show that the spectral and radial distribution of the nonthermal emission of massive, M>10^{14.5}M_sun, galaxy clusters (GCs) may be approximately described by simple analytic expressions, which depend on the GC thermal X-ray properties…
The compact stellar clusters have emerged as particularly promising candidates for cosmic rays (CR) accelerators. The star clusters, recently observed in gamma-rays, are also known sources of non-thermal X-ray emission, which is due to…
Properties of high redshift clusters are a fundamental source of information for cosmology. It has been shown by Oukbir and Blanchard (1997) that the combined knowledge of the redshift distribution of X-ray clusters of galaxies and the…
Clusters of galaxies contain a hot gas, which emits in X-rays. X-ray telescopes such as XMM-Newton allow to study this plasma to obtain information on physical quantities of these objects. We present here some results on the total mass…
The interaction of magnetic turbulence and relativistic particles is a important process for understanding particles propagation and acceleration in many astrophysical environments. Large-scale turbulence can be generated in the…
Galaxy clusters, the largest clearly defined objects in our Universe, are ideal laboratories to study in detail the cosmic evolution of the intergalactic intracluster medium (ICM) and the cluster galaxy population. For the ICM, which is…
(Abridged) The main purpose of this paper is to consider the contribution of all three non-thermal components to total mass measurements of galaxy clusters: cosmic rays, turbulence and magnetic pressures. To estimate the thermal pressure we…
Evidence for non-thermal activity in clusters of galaxies is well established from radio observations of synchrotron emission by relativistic electrons. New windows in the Extreme Ultraviolet and Hard X-ray ranges have provided for more…
Clusters of galaxies are used in a variety of ways to do cosmology. Some of them are presented here. Their X-ray emitting gas allows us to determine the baryon fraction, dark matter distribution and the matter density $\Omega_{m}$ of the…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Mergers drive shocks into the intracluster gas, and…
We report the first localization of diffuse, non-thermal, X-ray emission from a nearby galaxy cluster. Using Chandra data, we have isolated a diffuse non-thermal X-ray component with a photon index, Gamma_ X = 2.21 +0.14 -0.15 and a flux of…
The X-ray emission from clusters of galaxies enables them to be used as good cosmological probes and as an example for massive galaxy formation. The gas mass fraction in clusters should be a universal standard which by means of Chandra…