Fast-neutron capture cross section data measurement of minor actinides for development of nuclear transmutation systems

Katabuchi, Tatsuya*; Iwamoto, Osamu  ; Hori, Junichi*; Kimura, Atsushi   ; Iwamoto, Nobuyuki  ; Nakamura, Shoji  ; Rovira Leveroni, G.   ; Endo, Shunsuke   ; Shibahara, Yuji*; Terada, Kazushi*; Kodama, Yu*; Nakano, Hideto*; Sato, Yaoki*; Matsuura, Shota*

Long-lived minor actinides (MA) in nuclear waste from nuclear power plants are a long-standing issue to continue nuclear energy production. To solve the issue, researchers have suggested nuclear transmutation, in which long-lived radionuclides are transmuted into stable or shorter-life nuclides via neutron-induced nuclear reactions. Development of nuclear transmutation systems as an accelerator-driven system requires accurate neutron nuclear reaction data. The present research project entitled "Study on accuracy improvement of fast-neutron capture reaction data of long-lived MAs for development of nuclear transmutation systems" have been conducted as a joint collaboration, including Tokyo Tech, Japan Atomic Energy Agency and Kyoto University. This project focuses on the neutron capture reaction of MAs, especially Np, Am and Am, in the fast neutron energy region. The final goal of this project is to improve the accuracies of the neutron capture cross sections of Np, Am and Am employing a high-intensity neutron beam from a spallation source of the Japan Proton Accelerator Research Complex (J-PARC) that reduces uncertainties of measurement. To achieve the goal, a neutron beam filter system in J-PARC, sample characteristic assay, and theoretical reaction model study were developed. In this contribution, the overview and results of the project will be presented.