We present the results of 4 simultaneous observations of Cygnus X-1 by Ginga and OSSE. The X-ray/γray spectra can be described by an intrinsic continuum and a component due to Compton reflection including an iron Kα line. The intrinsic spectrum at X-ray energies is a power-law with a photon spectral index of Γ = 1.6. The intrinsic γ-ray spectrum can be phenomenologically described by either a p...

Using Chandra observations, we study the X-ray emission of the stellar population in the compact dwarf elliptical galaxy M32. The proximity of M32 allows one to resolve all bright point sources with luminosities higher than 8 × 10 33 erg s −1 in the 0.5–7 keV band. The remaining (unresolved) emission closely follows the galaxy's optical light and is characterized by an emissivity per unit stell...

We report the results of the Suzaku X-ray observation of XSS J12270–4859, one of the hard X-ray sources in the INTEGRAL catalogue. The object has been classified as an intermediate polar (IP) by optical spectra and a putative X-ray period of ∼860 s. With a 30 ks exposure of Suzaku, we obtained a well-exposed spectrum in the 0.2–70 keV band. We conclude against the previous IP classification bas...

We review the current observational status of the M87 jet at radio, optical, and X-ray frequencies. Special attention is paid to the radio morphology, the radio-to-X-ray spectrum, measurement of proper motions, and optical evidence for a counter-jet. The problem of jet confinement is discussed, as well as models for the radio-to-X-ray spectrum and the related problem of particle lifetimes. Fina...

We present a broad band X-ray observation of the Cas A supernova remnant, obtained with the 4 narrow field instruments on board the BeppoSAX satellite. The X-ray spectrum thus obtained spans more than two decades in energy, from ≃ 0.5 to ≃ 80 keV. The complete spectrum is fit with a two-component non-equilibrium ionization (NEI) model plus a power-law component which dominates at the higher ene...

From the analysis of a ∼100 ks Chandra observation of the dwarf starburst galaxy NGC 1569, we have found that the X-ray point sources, CXOU 043048.1+645050 and CXOU 043048.6+645058, showed significant time variability. During this observation, the X-ray flux of CXOU 043048.1+645050 increased by 10 times in only 2 × 10 s. Since the spectrum in its bright phase was fitted with a disk blackbody mo...

We present in this paper analyses of the ROSAT PSPC and ASCA SIS and GIS observations of the Crab-like supernova remnant (SNR) G54.1+0.3. Its spectrum obtained by ROSAT PSPC favors a power law model with a photon index of -0.8 −2.0, absorbed energy flux in 0.1-2.4 keV of 1.0×10 erg cm s, and absorption column density of 12.3 −3.2 × 10 21 cm. ASCA SIS observation shows that its spectrum can also...

We analyse five observations of the BL Lac object AO 0235+16 performed with the Chandra and XMM-Newton satellites during the years 2000–2005. In the February 2002 observation the source is found in a bright state and presents a steep X-ray spectrum, while in all the other epochs it is faint and the spectrum is hard. The soft X-ray spectrum appears to be strongly absorbed, likely by the interven...

LLE Review, Volume 152 184 Introduction The performance of inertial confinement implosions on OMEGA is potentially limited by the production of hot electrons.1 The hard x-ray image-plate (HXIP) diagnostic2 is used to determine the energy distribution of the hot electrons by estimating the spectrum of the x rays that are generated through bremsstrahlung with the target. Simulations and data from...