Year
2014
Abstract
he UF 6 Coincidence Counter (UFCC) is a 3 He - based nondestructive assay (NDA) system that was developed at Los Alamos National Laboratory (LANL) and is designed to measure Model 5A and 5B cylinders of uranium hexafluoride (UF 6 ). The measurement function of the UFCC is to determine the 235 U content of UF 6 inside the cylinders. The passive singles count rate and doubles - to - singles (D/S) ratio both provide a measure of 235 U mass in UF 6 . These two signatures, which are obtained simultaneously, have complementary advantages that can be used together to provide more overall confidence in the 235 U mass value than each signature provides when used individually. If the 235 U mass is combined with the total uranium mass from a scale, then the enrichment level in the cylinder can also be calculated. The measure ment approach for the UFCC can stand alone in passive mode, but it can also be used as an active interrogation system in order to measure 235 U enrichment directly. This paper covers the design and preliminary benchmark measureme nts of the UFCC.