Development of a 4 germanium spectrometer for nuclear data measurements at J-PARC

Kin, Tadahiro; Furutaka, Kazuyoshi  ; Goko, Shinji; Harada, Hideo   ; Igashira, Masayuki*; Kamiyama, Takashi*; Katabuchi, Tatsuya*; Kimura, Atsushi   ; Kino, Koichi*; Kitatani, Fumito  ; Kiyanagi, Yoshiaki*; Koizumi, Mitsuo ; Mizumoto, Motoharu*; Nakamura, Shoji  ; Ota, Masayuki; Oshima, Masumi; Toh, Yosuke   

For development of advanced reactors such as fast breeder reactors or accelerator driven systems, nuclear data of minor actinides (MAs) and long-lived fission products (LLFPs) are important for calculation of burning rates of fuels and transmutation rates to reduce the radio-toxicity of wastes. However, these data are insufficient at present in quantity and quality. To overcome/improve such a situation, we developed a 4 germanium spectrometer to measure neutron capture cross sections of MAs and LLFPs by time-of-flight measurements using pulsed neutron beams. At the conference, we will report details of the arrangement and characteristics of the spectrometer, such as detection efficiency, energy resolution and signal-to-background ratio, using results of measurement of standard sources. We will also show example of TOF spectra to report time resolution.