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

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

The purposes of this study are to perform Neutron Resonance Absorption NRA test experiments using the Micro Pixel Chamber, and to confirm its quantitativity. The detector was located at 14.5 m from the moderator in the experimental room of NOBORU. The samples, consisting of thin Tantalum (Ta) foils, with thicknesses of 5, 10, 20 and 100 m, were placed individually at 15 cm upstream from the detector. In the experiment, the transmission spectra with the Ta samples and no sample were obtained. Background components were not so small in these measurements. From the neutron transport simulation, it was surmised that the origin of this background was due to scattering of neutrons in the experimental room. Therefore, the assumed background components were subtracted from the measurement data. Finally, it was found that the difference between the measurement data and the nuclear data was within about 7%.