Criticality and Reactivity Measurement Method for Nuclear Material Control and Accountability

The authors describe the criticality and reactivity measurement method (CRMM) and give results of their analysis obtained by using this method for a physical inventory of nuclear materials (NMs) on the Nartsiss critical assembly at the Russian Research Center Kurchatov Institute (RRC KI). The proposed approach is a further development of the criticality measurement method used at the Los Alamos National Laboratory (LANL), and is a joint effort of LANL and RRC KI. A brief description is given of the Nartsiss critical assembly. Statistical control charts are used to study the reproducibility of results. The contributions of individual components to the resultant error of the proposed method are estimated. The method of quantile estimates of random errors is used in error analysis. It is shown that the CRMM has high sensitivity and may be successfully used in NM control and accountability.