Verification of more general correspondence between eigenvalue separation and coupling coefficient

Abstract

By taking neutron importance function as a new base of evaluating the coupling magnitude, and by identifying the boundary of a constituent core by zeroes of the first spatial mode, a generalized relation between coupling coefficients and eigenvalue separation is derived. By this equality one can obtain a unified, consistent view in the treatment of a large single core whose two partial zones are loosely coupled, and that of a two-core system with the two physically separated.