Optimised energy group structures for fusion activation calculations

Abstract

This study utilises self-shielding factors as a means to optimise energy group structures for fusion activation calculations. Informed by an analysis of important fusion resonances and a survey of relevant incident particle spectra, we develop and test two new group structures designed to more accurately represent the physics of nuclear reactions. They are compared to group structures commonly used in fusion research & analysis. When used in a JET activation foil scenario, the optimised group structures outperform reference group structures, such as CCFE-709, while requiring fewer bins.