DOSE ATTENUATION BY SOILS AND CONCRETE FOR BROAD, PARALLEL-BEAM NEUTRON SOURCES

摘要

This report presents the theory and results of certain neutron shielding studies performed to supply information primarily for underground bomb shelter design. Specifically, for neutron source energies of 0.025 ev, 0.5 Mev, 2.5 Mev, 7.5 Mev, 10 Mev, and 14 Mev, and various angles of incidence upon the ground, results are presented that show the total neutron plus secondary gamma dose rates which would be received by individuals located in shelters at various distances below ground. To cover the entire range of possibilities, four basically different soil types were analyzed with water contents ranging from zero to saturation. This range also includes concrete. Also, dose rates were calculated for depths ranging from 30 to 1,000 grams/cm2.