Thick target neutron yield at 0 degree by 250 and 350 MeV protons

Iwamoto, Yosuke   ; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Nakamura, Takashi*; Nakane, Yoshihiro  ; Nakashima, Hiroshi; Satoh, Daiki   ; Yashima, Hiroshi*; Yamakawa, Hiroshi*; Oishi, Koji*; Tamii, Atsushi*; Hatanaka, Kichiji*

Neutron energy spectra at 0 degree produced from stopping-length thick graphite, aluminum, iron and lead targets bombarded by 250 MeV and 350 MeV protons were measured at the neutron TOF course at RCNP of Osaka University. The neutron energy spectra were obtained by using the time-of-flight technique in the energy range from 10 MeV to incident proton energy. To compare the experimental results, Monte Carlo calculations by the PHITS and MCNPX codes using the JENDL-HE and the LA150 evaluated nuclear data files were performed. It was found that these calculated results at 0-degree generally underestimated the experimental results for all targets in the energy range above 20 MeV.