부산대학교 도서관

Several recent analyses using the multigroup MORSE Monte Carlo code are presented. In the calculation of a highly directional-dependent neutron streaming experiment it is shown that P{sub 7} cross section representation produces results virtually identical with those from an analog code. Use has been made here of a recently released ENDF/B-VI data set. In the analysis of neutron distributions inside the water-cooled ORELA accelerator target and positron source, an analytic hydrogen scattering model is incorporated into the otherwise multigroup treatment. The radiation from a nuclear weapon is analyzed in a large concrete building in Nagasaki by coupling MORSE and the DOT discrete ordinates code. The spatial variation of the DOT-generated free-field radiation is utilized, and the building is modeled with the array feature of the MORSE geometry package. An analytic directional biasing, applicable to the discrete scattering angle procedure in MORSE, is combined with the exponential transform. As in more general studies, it is shown that the combined biasing is more efficient than either biasing used separately. Other tracking improvements are included in a difficult streaming and penetration radiation analysis through a concrete structure. Proposals are given for the code generation of the required biasing parameters.