WU, M (reprint author), CHINESE ACAD SCI,INST HIGH ENERGY PHYS,HIGH ENERGY ASTROPHYS LAB,BEIJING,PEOPLES R CHINA.
Simulation calculations have been made Lo examine the modification effect of a hot X-ray photon field on a gamma-ray spectrum by the photon-photon pair production and inverse Compton scattering processes. The Cyg X-3 system was used as a paradigm. It is shown that a gamma-ray spectrum can change significantly when passing through the ambient keV X-ray photon field of an accretion binary source. For Cyg X-3, a significant amount of r-rays originated near the central source in the range of 10(2)-10(4) MeV could be absorbed by the extended X-ray photons from accretion disk corona in a high X-ray luminosity state and, on the other hand, the inverse Compton effect of secondary electrons could cause a considerable increase in intensity of gamma-rays between approximately 10 MeV and approximately 50 MeV. The relevance of the absorption effect for observations is discussed.