A mixed energy-group, energy-point formalism for neutron slowing-down problems

An accurate alternative method to energy-multigroup theory for slowing-down problems is considered in which a particular energy range is represented by discrete energy points while the larger part of the energy range is treated by groups. Applications of the technique are made for homogeneous iron-sodium and uranium-graphite mixtures, and for two-region cells composed of these materials. It is demonstrated that by suitable distribution of the energy points within the selected energy range, reaction rates and their temperature coefficients can be predicted with better accuracy than the conventional multigroup method of treating the energy range as a single group.