One of the most important advances in high-energy astrophysics over the past decade has been the detailed understanding that has emerged of the nature of binary stellar systems in which material from an ordinary star is being accreted on to a compact object, either a neutron star or a black hole[1,2]. These systems are called ‘X-ray binaries’ because emission from the accretion disk and associa...

Chandra observations of the X-ray–faint elliptical galaxy NGC 4697 resolve much of the X-ray emission (61% within one effective radius) into ∼80 point sources, of which most are low-mass X-ray binaries (LMXBs). These LMXBs provide the bulk of the hard emission and much of the soft emission as well. Of the remaining unresolved emission, it is likely that about half is from fainter LMXBs, while t...

The first X-ray survey of the Large Magellanic Cloud (LMC) was performed with the Einstein satellite, revealing diffuse X-ray emission from hot gas and discrete X-ray sources. The ROSAT observations between 1990 and 1998 supplied the most sensitive survey with imaging instruments in the soft X-ray band (0.1 2.4 keV). The PSPC and HRI observations covered 59 square degrees of the LMC and yielded...

The stellar winds flowing out of the components of WR + OB binaries can collide and the shock waves are formed. Stellar wind collision, particle acceleration by the shocks and generation of X-ray, γ-ray, radio and IR emission in WR + OB binaries are discussed.