MOMENTS OF MULTIPLE-SCATTERING

We present an analytical technique that solves exactly, and in closed form, for the first and second moments of the spatial and angular posi tions of photon distributions in a multiple-scattering medium. The ana lysis leads to simple analytic expressions for these moments, both con ditioned on the number of scatterings and summed over all scattering e vents. The conventional results for small-angle forward scattering, an d for the diffusion regime, are recovered in the appropriate limiting cases. (C) 1995 Optical Society of America