Development of a table-top NRTA system, 2; Monte Carlo study for Pu pellet sample measurement

卓上型中性子共鳴透過分析装置の開発,2; Puペレット試料測定のためのシミュレーションによる検討

Guembou Shouop, C. J.  ; 土屋 晴文 

Guembou Shouop, C. J.; Tsuchiya, Harufumi

Neutron Resonance Transmission Analysis (NRTA) is a promising nondestructive assay technique to determine the quantities of uranium, plutonium, higher-order actinides, and fission products in spent fuel. However, existing NRTA systems are large and therefore impractical. Downsizing the NRTA system for mobility and in-situ assessment could be achieved via spontaneous fission neutron radioactive sources such as Cf, which require appropriate collimation systems. In this presentation, Monte Carlo studies assessed the capability of NM detection in small samples such as Pu pellets. Time-of-flight spectra obtained with a Pu pellet sample showed resonance dips for polyethylene containing and polyethylene containing LiF collimator types whereas those for polyethylene and air have no clear resonance dips. These results indicated that the table-top NRTA system under development can effectively detect Pu nuclides in small samples such as Pu pellets, considering PE- configuration. This research was implemented under the subsidy for nuclear security promotion of MEXT.