Demonstration Plan of Pu NDA System using ZnS Ceramic Scintillator

To establish an alternative technique of He-3 neutron detector that is used for nuclear material accountancy and safeguards, we have started an R&D project to develop a new type of neutron detector (Pu NDA system) using ZnS ceramic scintillator with support of Japanese government. The design of the alternative system is basically referenced from PCDF-PCAS (Plutonium Canister Assay System) which has total 22 He-3 tubes and can measure up to 5kgPu mass in a MOX canister. In order to prove the technology and performance after the fabrication of the new detector progresses, we are planning to conduct 2 stage of demonstration activity in the near future experimentally. The first stage of demonstration activity implements the confirmation of flatness response profile for vertical axis, integrity check of detector parameters and basic performance comparison between calculated and measured using MOX powder around June 2013. After some modification and upgrade will have completed, we will conduct second stage of demonstration activity around December 2013. During the activity, we plan to perform the performance comparison between current PCAS and the new Pu NDA related to the counting statistics. In addition, calibration by known-alpha technique and the uncertainty evaluation of Pu measurement for the new Pu NDA are also implemented. It is estimated that the historical difference between measured (PCAS) and declared (DA based) in the current PCAS is about +/- 2%. It is expected that the new Pu NDA system have more consistent between them for establishment of alternative technology instead of He-3 neutron detector.