Scattering by gamma-distributed phase screens

Abstract

The multipoint statistics of a joint gamma process are investigated. Analytical expressions are derived for the generating functions of the fourfold probability densities of the process and results are also obtained for its slope statistics. The results are used to characterize the wavefront distortion introduced into an incident beam of radiation by a phase changing screen and the scintillation index of the scattered intensity in the Fresnel region is calculated for various spectral models. Properties of the ray density functional are also investigated for the sub-fractal case when the wavefront is once differentiable.