Performance of a 4π Ge spectrometer for neutron capture cross section measurements

Neutron capture cross sections of minor actinides and long-lived fission products are important for the R&D of innovative nuclear reactors. However, those data are rather poor both in quality and in quantity at present. Thus, we have started projects for neutron cross section measurements. We have constructed an 4π Ge spectrometer consisting of Ge crystals and BGO shields. The neutron cross section measurements have been done at KURRI electron linac and JAEA JRR-3 facilities, which will be extended at the high-intensity neutron source at J-PARC.