相关论文: On the magnetic fields and particle acceleration i…

We propose a model for the hard X-ray (> 10 keV) emission observed from the supernova remnant Cas A. Lower hybrid waves are generated in strong (mG) magnetic fields, generally believed to reside in this remnant, by shocks reflected from…

We report on our analysis of the 1 Ms Chandra observation of the supernova remnant Cas A in order to localize, characterize and quantify its non-thermal X-ray emission. More specifically, we investigated whether the X-ray synchrotron…

The radio galaxy Cen A has been detected all the way up to the TeV energy range. This raises the question about the dominant emission mechanisms in the high-energy domain. Spectral analysis allows us to put constraints on the possible…

We study the origin of the non-thermal emission from the intracluster medium, including the excess hard X-ray emission and cluster-wide radio haloes, through fitting two representative models to the Coma cluster. If the synchrotron emitting…

Recently, the High Altitude Water Cherenkov (HAWC) collaboration reported the discovery of the TeV halo around the Geminga pulsar. The TeV emission is believed to originate from inverse Compton scattering of pulsar-injected…

The recent detection of a hard X-ray component in the supernova remnant Cassiopeia A is interpreted as synchrotron emission from electrons accelerated to energies up to 40 TeV (Allen et al., 1997). It is therefore tempting to consider TeV…

Based on the results of our previous study of the broad band synchrotron emission of Cas A in the framework of a spatial inhomogeneous model, we calculate the fluxes of gamma-radiation that can be expected from this supernova remnant in…

Cassiopeia A (Cas A) as the nearby young remnant of a core-collapse supernova is the best candidate for astrophysical studies in supernova explosion and its environment. We studied hard X-ray emissions from Cas A using the ten-year data of…

Combining archival data taken at radio and infrared wavelengths with state-of-the-art measurements at X-ray and gamma-ray energies, we assembled a broadband spectral energy distribution (SED) of Cas A, a young supernova remnant. Except for…

We use the Chandra X-ray Observatory to study the region in the Tycho supernova remnant between the blast wave and the shocked ejecta interface or contact discontinuity. This zone contains all the history of the shock-heated gas and…

A variety of models have been explored in regard to the origin of the excess extreme ultraviolet (~ 0.1 keV) emission in the Coma cluster. It is now established that the flux is non-thermal and the only non-thermal source mechanism that…

We consider in more detail a model previously proposed for the hard X-ray (>10 keV) emission observed from the supernova remnant Cas A, whereby electrons are accelerated by lower-hybrid waves and radiate bremsstrahlung. We consider both…

Non-thermal X-ray emission from the shell of Cassiopeia A (Cas A) has been an interesting subject of study, as it provides information about relativistic electrons and their acceleration mechanisms in the shocks. Chandra X-ray observatory…

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,…

We present multi-epoch Ks band imaging of the supernova remnant Cassiopeia A (Cas A). The morphology of the emission in this band is generally diffuse and filamentary, consistent with synchrotron radiation observed at radio wavelengths.…

We discuss the extended X-ray emission seen in three archival Chandra observations, and one archival XMM-Newton observation, of the FRII radio galaxy Pictor A. The overall properties of the X-ray lobes are consistent with the conclusions of…

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…

The processes responsible for the broad-band radiation of the young supernova remnant Cas A are explored using a new code which is designed for a detailed treatment of the diffusive shock acceleration of particles in nonlinear regime. The…

The detection of unpulsed TeV emission from PSR B1706-44 raised the question if this VHE emission results from inverse Compton scattering of multi-TeV electrons on the CMBR and other soft photon fields. This hints at the existence of an…

The different electron distributions in the hard and soft spectral states (HS and SS) of BH binaries could be caused by kinetic processes and changing because of varying physical conditions in the corona. In presence of a magnetic field in…