  We consider a formulation of Cauchy problem for Kolmogorov equation which
corresponds a localized source of particles to be scattered by medium with
given scattering amplitude density. The multiple scattering amplitudes are
introduced and the corresponding series solution of the equation is
constructed. We investigate the one-fold integral representation for the series
terms, its estimations and values of photon number of a finite and point
receivers. An application to X-ray beam scattering for orthogonal and inclined
to a layer is considered.
