Related papers: Modelling the non-thermal emission from galaxy clu…
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…
Although pulsars can radiate electromagnetic wave from radio to gamma ray bands, we still have no a united model to understand the multi-band emission. In this paper the effort for a joint model is presented. The inverse Compton scattering…
This paper is a brief review of the processes responsible for X-ray emission from radio jets, lobes and hot spots. Possible photons in inverse Compton scattering models include the radio synchrotron radiation itself (i.e. synchrotron…
Cooling flows are regions where the importance of non-thermal intra-cluster medium components such as magnetic fields and cosmic rays may be strongest within a galaxy cluster. They are also regions where such components are best detectable…
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…
A new study of the diffuse Galactic gamma-ray continuum radiation is presented, using a cosmic-ray propagation model which includes nucleons, antiprotons, electrons, positrons, and synchrotron radiation. Our treatment of the inverse Compton…
X-ray observations of galaxy clusters potentially provide powerful cosmological probes if systematics due to our incomplete knowledge of the intracluster medium (ICM) physics are understood and controlled. In this paper, we study the…
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…
Faraday rotation measures (RMs) of extragalactic radio sources provide information on line-of-sight magnetic fields, including contributions from our Galaxy, source environments, and the intergalactic medium (IGM). Looking at differences in…
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 important evidences for non-thermal phenomena in galaxy clusters comes from the spectacular synchrotron radio emission diffused over Mpc scale observed in a growing number of massive clusters. A promising possibility to explain…
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…
We present a numerical approach to investigate the relationship between magnetic fields and Faraday rotation effects in clusters of galaxies. We can infer the structure and strength of intra-cluster magnetic fields by comparing our…
We report the detection of both soft and hard excess X-ray emission in the cluster of galaxies A 2199, based upon spatially resolved spectroscopy with data from the BeppoSAX, EUVE and ROSAT missions. The excess emission is visible at radii…
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…
Analysis of the radio synchrotron and X-ray inverse-Compton emission from radio-loud active galaxies allows us to determine their particle acceleration processes and electron energy spectra. Previous studies have provided new constraints on…
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…
We present a study of the rotation measure (RM) obtained from a sample of extra-galactic radio sources either embedded in or seen in projection through a sample of seven southern galaxy clusters (declination less than 30 degrees). We…
(Abridged) High-E electrons produce Hard X-Ray (HXR) emission in galaxy clusters by via Inverse Compton Scattering (ICS) of CMB photons. We derive the ICS HXR emission of Ophiuchus under various scenarios: primary cosmic ray model,…
Context. The diffuse X-ray emission surrounding radio galaxies is generally interpreted either as due to inverse Compton scattering of non-thermal radio-emitting electrons on the Cosmic Microwave Background (IC/CMB), or as the thermal…