An integral experiment on thorium oxide/depleted uranium cylinders with D-T neutrons for 232Th(n, 2n) reaction

In order to verify the evaluated cross sections of Th-232(n, 2n) reaction for the conceptual design of the thorium based subcritical blanket in the fusion-fission hybrid reactor, an integral experiment on thorium oxide/depleted uranium cylinders was carried out with D-T neutrons using the activation technique. Th-232(n, 2n) reaction rate distribution was obtained at the central axis direction in the assemblies with an uncertainty of about 7%. Experiments were analyzed by using MCNP code with ENDF/B-VI.8, ENDF/B-VILO, JENDL-4.0 and CENDL-3.1 libraries to validate the nuclear data libraries of Th-232(n, 2n) reaction, the calculated results with JENDL-4.0 agree with the measurements the best with discrepancies within the experimental uncertainty. The average values of CIE for the three benchmark assemblies are 1.058, 1.044 and 0.980. Calculations with different evaluated libraries in the benchmark assemblies show a large discrepancy. The experimental results can be used to re-evaluate the cross sections of the Th-232(n, 2n) reaction. (C) 2015 Elsevier Ltd. All rights reserved.