Local separation of angle and energy in one-dimensional transport

The authors report a highly efficient and accurate method for solving the transport equation in slab or sphere geometries. The complete information carried by the angular flux Ψ is rarely needed. In fact, to calculate reaction rates, leakage rates, etc., one needs only the zeroth and first moments of Ψ. The aim is to reduce the role of Ψ to a minimum. The basic assumption underlying the method is the local separability of the angular and energy dependence of Ψ within an energy group.