Simplified P N and A N methods in neutron transport

Abstract The paper deals with general properties of the odd-order SP N equations. The equivalence between these equations and the so-called A N equations is demonstrated. The A N equations have the simple structure of a system of multigroup diffusion equations and are easily transformed into a set of boundary integral equations, which allows to apply a boundary element-response matrix solution technique and obtain a proper setting for the proofs of the boundary and interface conditions which are to be used. Some sharper results for the special class of the transport problems in which the total cross section is constant are discussed.