Quasi-monoenergetic neutron beam and its application at the RCNP cyclotron facility

Iwamoto, Yosuke   ; Yashima, Hiroshi*; Satoh, Daiki   ; Hagiwara, Masayuki*; Iwase, Hiroshi*; Nakamura, Takashi*; Shima, Tatsushi*; Tamii, Atsushi*; Hatanaka, Kichiji*

A quasi-monoenergetic neutron field using Li(p,n) reaction for the higher energy range of 100 to 400 MeV has been developed at the RCNP cyclotron facility of Osaka University. The neutron energy spectra at angles from 0 to 30 have been investigated for the proton beams with the energies of 140, 250, 350 and 392 MeV. The highest neutron fluence reaches 1.0 10 n/sr/C, and the contribution of peak intensity to the total intensity varied between 0.4 and 0.5. Using the quasi-monoenergetic neutron beam, measurement of neutron induced activation cross sections, elastic scattering cross sections for neutron and a shielding benchmark experiment have been performed, successfully. Thus quasi-monoenergetic neutron field at RCNP are suitable for measurement of nuclear data, shielding experiments and the calibration of monitors in the energy region from 100 to 400 MeV.