KeV-GeV emission in Cyg X-3 and Cyg X-1

I will discuss models of the GeV and TeV emission from X-ray binaries,
discovered in the TeV range by the HESS and MAGIC telescopes, and
observed now in the GeV range by Fermi. In the case of PSR B1259-63,
LS I +61 303 and LS 5039, the most likely model of the observed
persistent emission is interaction of the electron-positron pair wind
emitted by a young pulsar with the stellar wind from the high-mass
Be/O companion. I will present a detailed model for LS I +61 303. On
the other hand, the accreting binaries Cyg X-1 and Cyg X-3 have also
been discovered to emit high energy gamma-rays. In these objects,
electrons are accelerated to very high energies in the vicinity of the
central black hole, and the observed emission appears to be Compton
scattering of the stellar photons.