Study of sample shape effects on neutron resonance transmission analysis

中性子共鳴透過分析法における試料形状の影響調査

Ma, F.; 土屋 晴文 ; 北谷 文人  

Ma, F.; Tsuchiya, Harufumi; Kitatani, Fumito

Neutron resonance transmission analysis (NRTA) is a non-destructive assay technique and has a potential to evaluate the amount of special nuclear materials in nuclear fuels such as fuel debris and spent fuel. Those fuels, especially debris would have an irregular shape. It is expected that such an irregular shape affects NRTA measurements. In order to study how a sample shape affects measurements of NRTA, experiments with a Cu-bar sample with different rotation angles were done at a neutron Time-Of-Flight (TOF) facility GELINA (Belgium). A resonance analysis code Refit was used to analyze measured transmission spectra for individual rotation angles. It was found that the experimental transmission was able to be well fitted by considering the effect of hole-fraction and irregularity. This research was implemented under the subsidiary for nuclear security promotion of MEXT.