The Delta Function Approximation in Radiative Transfer Theory

Abstract

We consider an approximation that is useful for solving the diffuse transmission and reflection problem when the phase function has a sharp forward peak. In this approximation the forward peak is truncated and compensated for by changing the volume scattering coefficient. It provides values for reflected and transmitted fluxes and intensities that are accurate to better than 1% for most angles and for widely differing values of the absorption and total optical depth.