Abstract
Abstract
In order to develop a general procedure, the scattering kernel is described in a consistent manner. By using this scattering kernel, eigenvalues and eigenfunctions and critical slab thicknesses are computed with a conventional spherical harmonics method (PN). The basis of this method relates to the generating function of Legendre polynomials. This article has improved analytical methods and numerical values. Numerical results indicate that the critical thickness varies with forward isotropic scattering. Results are discussed and compared with isotropic and anisotropic results using various methods available in the literature. Eigenvalues and critical thicknesses are calculated using the new phase function instead of conventional expansions.