AbstractSimple empirical-analytical formulas for 14-MeV and fast (E > 0.1 MeV) neutron fluxes at the exit from a radiation shield with a straight-through diagnostic channel are proposed. The results are consistent with previous calculations with the two-dimensional DOT3 code. Attenuation lengths λ required to characterize the attenuation along the shield thickness were obtained for numerous shield types. These data could be used both for quick evaluation of shield effectiveness and for comparison of different shield types. This study is based on the numerous results of neutron transport calculations obtained in Russia for the last ten years (since 1982 to 1991) by the analysis of the radiation shields of experimental thermonuclear reactors, namely INTOR, ITER/OTR, ITER etc. The study is carried out in Japan by analysis and generalizing of the above-mentioned results.
Neutronics for ITER diagnostic systems and ports