AN ANALYTICAL DERIVATION OF TRANSPORT-CORRECTED P_0 CROSS SECTIONS AND DIFFUSION COEFFICIENTS

摘要

Previous work by Herman et al.has described the computation of diffusion coefficients for hydrogen via the numerical solution of a 1-D, fixed-source transport problem. It has also been shown that these diffusion coefficients can be used to obtain accurate transport-corrected P_0 cross sections for hydrogen. In this paper, we present a new and more general analytical approach for the derivation of the diffusion coefficients from. We show analytically and numerically that, when the appropriate parameters are chosen, the analytical approach yields diffusion coefficients that are nearly identical to those in. The analytic approach is less computationally expensive than the method described in, and it illuminates the physics behind the computation of these diffusion coefficients. We also show that this analytical approach is equivalent to the in-scatter method provided the buckling is neglected and the neutron current energy spectrum from the analytical approach is used. Due to a page limitation imposed on this paper, the authors removed an Appendix and made several other changes that marginally reduced the information content of the mathematical analysis.