Analysis of integral experiment for Th-232 (n, γ) reaction cross section at KUCA

To measure integral neutronics characteristics of thorium loaded core, critical experiments had been carried out using Kyoto University Critical Assembly (KUCA). The critical experiments were performed with various neutron spectrums and thorium inventories. The thorium loaded cores has two regions which are a test zone and a driver fuel zone. The test zone consists of thorium plates and graphite plates. In order to systematically vary the neutron spectrum of the experimental neutron field, the graphite/Th-232 ratio at the test zone had been systematically varied by changing the combination of the thorium plates and the graphite plates in a unit cell. In this study, the criticalities of thorium loaded core were analyzed by MVP2.0 with JENDL-4.0, JENDL-3.3 and ENDF/B-VII.0. In addition, sensitivity analyses were performed by SAGEP and uncertainties of the numerical results were evaluated using cross section covariance matrix. (author)