Quantitative measurements of element distributions using neutron-transmission resonance-absorption method

Harada, Masahide   ; Parker, J.*; Sawano, Tatsuya*; Kubo, Hidetoshi*; Tanimori, Toru*; Shinohara, Takenao   ; Maekawa, Fujio  

Neutron Resonance Absorption method (NRA) which is one of the imaging methods is very suitable for nondestructive analysis of element distributions in a sample. In this study, the NRA test experiments used by Micro Pixel Chamber (PIC) developed by Kyoto University as a detector were done at NOBORU in J-PARC to confirm the quantitativity. The detector was located at 14.5 m from the moderator. A sample was located at 15 cm upstream from the detector. Neutron intensity, neutron irradiation field size and -ray intensity were controlled by a rotary collimator, slits and a filter exchange device. Thin tantalum foils of 20 m and 100 m in thickness were used as a sample. Transmittance spectra were obtained from the measured transmission spectra with and without the samples. It was found that the measurement error in case of the tantalum sample of 100m in thickness was within about 7% compared with nuclear data.