Benchmark experiment for bismuth by slab samples with D-T neutron source

Abstract

A benchmark experiment is carried out with slab sample to validate nuclear data of bismuth by measurement of leakage neutron spectra from 0.8–16 MeV. The measured experiments are performed at China Institute of Atomic Energy with the integral benchmark facility established on the D–T neutron generator. The neutrons leaking from the sample are recorded at the measuring angle of 60° and 120° by time-of-flight technique. To make understanding of the impact of accuracy of data files in evaluated library on the neutron transport simulation, the calculation is carried out by MCNP-4C code with a series of latest available evaluated libraries. The calculated spectra are analyzed by comparing with experimental ones in neutron spectrum shape and C/E values. The result indicates that the theoretical simulation with different data libraries overestimated or underestimated the measured ones in some energy ranges, and the secondary neutron energy distribution and angular distribution in data files have been present to explain it.