title: Characteristics of high-energy neutrons estimated using the radioactive spallation products of Au at the 500-MeV neutron irradiation facility of KENS.
abstract: We carried out a shielding experiment of high-energy neutrons, generated from a tungsten target bombarded with primary 500-MeV protons at KENS, which penetrated through a concrete shield in the zero-degree direction. We propose a new method to evaluate the spectra of high-energy neutrons ranging from 8 to 500 MeV. Au foils were set in a concrete shield, and the reaction rates for 13 radionuclides produced by the spallation reactions on the Au targets were measured by radiochemical techniques. The experimental results were compared with those obtained by the MARS14 Monte-Carlo code. A good agreement (between them) was found for energies beyond 100 MeV. The profile of the neutron spectrum, ranging from 8 to 500 MeV, does not depend on the thickness of the concrete shield.
authors.affiliation: High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan. hiroshi.matsumura@kek.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsumura
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Masumoto
authors.forename: Noriaki
authors.initials: N
authors.lastname: Nakao
authors.forename: Qingbin
authors.initials: Q
authors.lastname: Wang
authors.forename: Akihiro
authors.initials: A
authors.lastname: Toyoda
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawai
authors.forename: Takahiro
authors.initials: T
authors.lastname: Aze
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Fujimura
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005214:Fast Neutrons; D006046:Gold / Q000528:radiation effects; D007564:Japan; D018499:Linear Energy Transfer; D008962:Models, Theoretical; D009010:Monte Carlo Method; D010315:Particle Accelerators / Q000295:instrumentation*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods*; D011868:Radioisotopes / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D006046:Gold