On the effect of coronal outflow on spectra formation in galactic black hole systems

We present the results of both analytical and numerical calculations of the amplitude of the reflection component in X-ray spectra of galactic black h ole systems. We take into account the anisotropy of Compton scattering and the systematic relativistic bulk motion of the hot plasma. In the case of t he single scattering approximation, the reflection from the disc surface is significantly enhanced owing to the anisotropy of Compton scattering. On t he other hand, the calculations of multiple scattering obtained using the M onte Carlo method show that the anisotropy effect is much weaker in that ca se. Therefore, the enhanced back-scattered flux may affect the observed spe ctra only if the disc surface is highly ionized, which reduces the absorpti on in the energy band corresponding to the first Compton scattering.