Benchmark experiment on copper with graphite by using DT neutrons at JAEA/FNS

Abstract

We had pointed out that the elastic scattering and capture reaction data of the recent nuclear data libraries for copper had included some problems in the resonance energy region, which had caused a large underestimation of reaction rates of non-threshold reactions. In order to corroborate this issue, we carried out a new benchmark experiment on copper in the neutron field with more low energy neutrons. We measured reaction rates using the activation foils and analyzed the experiment with MCNP5.140 and ENDF/B-VII.1, JEFF-3.2 and JENDL-4.0. As a result, the calculated reaction rates related to low energy neutrons excessively underestimated the measured ones as in the previous experiment. The calculated reaction rates with the modified copper nuclear data in the previous study reproduced the measured ones well. However, it was revealed that the modified copper data needed more revision.