Radial Distribution of Photons Backscattered from the Surface of Semi-Infinite Scatterer

Abstract

The radial distribution of photons backscattered in the direction perpendicular to the front face of a semi-infinite scatterer was examined for the case of a point isotropic r-source placed on the scatterer. As a result, the following relations were found:/ ' where N.(r) and 1.(r) respectively are the fractions of photons and energies emerging perpendicularly at a point r.Monte Carlo calculations by collision density method was performed to confirm the validity of the above relations, as well as to verify that the radial distribution of photons backscattered in all directions from the slab surface is subject to the same relations as above.The values of the constants a. and b. obtained by experiment were rather smaller than those by calculation, but the values of the constants for the radial distribution of photons backscattered in all directions were nearly equal to those for the normal direction. The relation between the values of the constants and the number and energy albedos was examined.