Measurement and analysis of induced activities in concrete irradiated using high-energy neutrons at KENS Neutron Spallation Source Facility.
Precise estimation of induced activities in concrete shields for high-energy accelerator facilities is one of the most important issues that need to be solved, not only for the reduction of exposure for workers, but also for the reduction of radioactive wastes. Irradiation experiments have been performed by using the 500 MeV Neutron Spallation Source Facility in KEK. The large concrete assembly was placed in the direction of 0 degrees to the beamline. Two kinds of samples were placed at several positions in the assembly. The irradiation period was about 1 week and induced activities in the samples were measured until approximately 1.5 y after irradiation. From the comparison between the experiment and the available Monte Carlo calculation code system, good agreement was obtained for 24Na, 47Sc, 47Ca and 54Mn within a factor 2; however, large discrepancies were observed for some other nuclides.
Oishi
Koji
K
Institute of Technology, Shimizu Corporation, Koto-ku, Tokyo 135-8530, Japan. koji_oishi@shimz.co.jp
Nakao
Noriaki
N
Kosako
Kazuaki
K
Yamakawa
Hiroshi
H
Nakashima
Hiroshi
H
Kawai
Masayoshi
M
Yashima
Hiroshi
H
Sanami
Toshiya
T
Numajiri
Masaharu
M
Shibata
Tokushi
T
Hirayama
Hideo
H
Nakamura
Takashi
T
D003198:Computer Simulation; D003252:Construction Materials / Q000032:analysis*; D019544:Equipment Failure Analysis; D018499:Linear Energy Transfer; D008422:Materials Testing; D015233:Models, Statistical; D009502:Neutrons; D010315:Particle Accelerators / Q000295:instrumentation*; D011829:Radiation Dosage; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D011874:Radiometry / Q000379:methods*