New integral experiment on vanadium using DT neutron at JAEA/FNS

Sato, Satoshi*; Kwon, Saerom*; Ota, Masayuki*; Konno, Chikara  

In order to validate the nuclear data library of vanadium, integral experiments on vanadium with the DT neutron source at JAEA/FNS were performed over 20 years ago. Some calculated reaction rates underestimated the measured ones in the previous study. Background neutrons scattered in the concrete wall of the experimental room are considered to cause these underestimations. In order to reduce background neutrons, we propose new experimental assemblies and perform new integral experiments on vanadium with the DT neutron source at JAEA/FNS in this study. A rectangular vanadium-alloy assembly of 152 mm in width, 136 mm in height and 152 mm in thickness is covered with LiO blocks to exclude background neutrons which might affect the measured data. Using activation foils and micro fission chambers, we measure the reaction rates of the Nb(n,2n)Nb, Al(n,)Na, In(n,n')In, Au(n,)Au, W(n,)W, U(n,f) and U(n,f) reactions. We analyze the experiment by using MCNP5-1.40 with JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2. All the calculation results generally show good agreement with the measured ones in this experiment. It is concluded that the nuclear data of vanadium have no problem.