Centaurus A at Hard X-Rays and Soft Gamma-Rays

Centaurus X - 3 — A Source of High Energy Gamma Rays

Centaurus X-3 is a well-studied high-mass accreting X-ray binary and a variable source of high energy gamma rays with energies from 100 MeV to 1 TeV. Previous results have suggested that the origin of the gamma rays is not the immediate vicinity of the neutron star but is sited in the accretion disc, perhaps in an accretion wake. The Durham Mark 6 gamma ray telescope has been used to measure th...

Unification of Active Galactic Nuclei at X-rays and soft gamma-rays

The unification of X-ray and radio selected BL Lacs has been an outstanding problem in the blazar research in the past years. Recent investigations have shown that the gap between the two classes can be filled with intermediate objects and that apparently all differences can be explained by mutual shifts of the peak frequencies of the synchrotron and inverse Compton component of the emission. W...

X-rays and Soft Gamma-rays from Seyferts, Radio Galaxies, and Black-Hole Binaries

Selected topics dealing with X-ray/soft γ-ray emission from accreting black-hole sources are reviewed. The shape of soft γ-ray spectra of Seyferts observed by OSSE can be well modeled by thermal Comptonization. A very strong correlation between the X-ray slope and the strength of Compton reflection in these sources can then be explained by thermal Comptonization in vicinity of the reflecting co...

Resonant Inelastic X-ray Scattering at the ESRF: Hard and Soft X-rays

Young stellar objects from soft to hard X-rays

Magnetically active stars are the sites of efficient particle acceleration and plasma heating, processes that have been studied in detail in the solar corona. Investigation of such processes in young stellar objects is much more challenging due to various absorption processes. There is, however, evidence for violent magnetic energy release in very young stellar objects. The impact on young stel...