Related papers: Limits on Magnetic Fields and Relativistic Electro…
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…
Models for the evolution of the integrated energy spectrum of primary cosmic ray electrons in clusters of galaxies have been calculated, including the effects of losses due to inverse Compton (IC), synchrotron, and bremsstrahlung emission,…
The spectral shape of radiation due to Inverse Compton Scattering is analyzed, in the Thomson and the Klein-Nishina regime, for electron distributions with exponential cut-off. We derive analytical, asymptotic expressions for the spectrum…
The limited angular resolutions and sensitivities historically available below 300 MHz have made it difficult to define the low end of the electron energy distribution, N(gamma). We extrapolate down from the well observed segments of radio…
The origin of the nonthermal EUV and hard X-ray emission "excess" reported from some galaxy clusters has been intensively debated over last several years. The most favored models which refer this excess to relativistic electrons…
We use deep archival Chandra and XMM-Newton observations of three of the brightest cluster-centre radio galaxies in the sky, Cygnus A, Hercules A and Hydra A, to search for inverse-Compton emission from the population of electrons…
We explore the possibility of detecting the excess of the cosmic radio background (CRB) toward galaxy clusters due to its Compton scattering by electrons of the hot intergalactic gas. When mapping the background fluctuations at frequencies…
X-ray emission due to inverse-Compton scattering of microwave background photons by electrons in the lobes of powerful radio galaxies has now been seen in a large number of objects. Combining an inverse-Compton model for the lobe X-ray…
Radio, X-ray, and gamma-ray observations provide us with strong evidence of particle acceleration to multi-TeV energies in various astrophysical sources. Diffusive shock acceleration is one of the most successful models explaining the…
With magnetic fields below one microgauss, the minimum pressures of synchrotron plasmas start to approach those in the thermal gas in cluster outskirts and the more diffuse WHIM in large-scale structure filaments. We summarize some of our…
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…
As energetic particles diffuse out of radio and star-forming galaxies (SFGs), their intracluster density builds up to a level that could account for a substantial part or all the emission from a radio halo. We calculate the particle…
We calculate the fluxes of radio, hard X-rays and gamma-ray emission from clusters of galaxies, in the context of a secondary electron model (SEM). In the SEM the radiating electrons are produced by the decay of charged pions in cosmic ray…
Many galaxy clusters have giant halos of non-thermal radio emission, indicating the presence of relativistic electrons in the clusters. Relativistic protons may also be accelerated by merger and/or accretion shocks in galaxy clusters. These…
We re-analyze the Chandra ACIS spectrum of the kpc-scale jet in PKS 0637-752 to investigate the possible low energy cutoff in the relativistic electron spectrum producing the non-thermal radiation in the scenario of inverse Compton emission…
We present constraints on the density of halo dark matter candidates within the solar circle based on the anisotropy in the high energy gamma-ray background. The known galactic components of the gamma-ray background, in particular the…
The backward Compton scattering is a basic process at future higher energy photon colliders. To obtain a high probability of e->gamma conversion the density of laser photons in the conversion region should be so high that simultaneous…
Some clusters of galaxies in addition to thermal bremsstrahlung (TB), emit diffuse radiation from the intercluster medium (ICM) at radio, EUV and hard x-ray (HXR) ranges. The radio radiation is due to synchrotron by relativistic electrons,…
Most of the Universe's populations of low energy cosmic ray electrons in the energy range of 1-100 MeV still manage to elude from detection by our instruments, since their synchrotron emission is at too low frequencies. We investigate a…
We present results from {\gamma}-ray observations of the Coma cluster incorporating 6 years of Fermi-LAT data and the newly released {\emph{Pass 8}} event-level analysis. Our analysis of the region reveals low-significance residual…