Investigation of Local Spectral Differences between Critical and Driven Sub - Critical Configurations in Muse - 4

Studies of spectral characteristics of different critical and driven sub-critical MUSE-4 configurations are presented in this paper. The current investigations have permitted to quantify important aspects, such as the influence of the intrinsic source, the asymmetry of the core along the north/south axis, the impact of the two different types of external sources to be employed, and the moderation/multiplication effects of the central diffusing lead region. One of the principal goals has been to define a suitable measurement programme using different threshold reaction rates and fission rate traverses (U and U). These measurements will constitute an important experimental database for validating the calculational methods and data employed for analysing the neutron coupling in these ADS-representative configurations.