Automated Template Matching Method for NMIS at the Y-12 National Security Complex

This paper describes a template matching method used by the Nuclear Materials Identification System (NMIS) to identify weapons components. The method is applied to NMIS's active source ({sup 252}Cf) radiation measurements for HEU components, utilizing four scintillation detectors. NMIS measures the spatial and temporal distribution of neutron and gamma radiation after a {sup 252}Cf fission. This method further processes these measurements to extract pattern recognition features for the matching algorithm, and finds the closest matching component in the NMIS library of reference component features (templates). This identification method is being developed for use at the Y-12 National Security Complex. The goal of this development is to obtain high accuracy with the constraints of short measurement times and a small number of reference template measurements.