SAMSY, Neutron and Gamma Dose Rates and Heat Source for Multilayer Shields

1 - Description of problem or function: The SAMSY code calculates multigroup neutron fluxes and dose rate, multigroup gamma ray dose rates and internal heat sources, as a function of distance through large multilayer reactor shields. 1-D geometries: plane, spherical, cylindrical. 2 - Method of solution: The code is based on Spiney method for neutron field analysis and on build-up factor method for gamma fields, with two optional approaches to build-up factors evaluation; the first is based on single layer build-up factor conception as in the well- known MAC-RAD code, and the second on the modified Harima-Nishiwaki formula for build-up factors in multilayered media. 3 - Restrictions on the complexity of the problem: 26 neutron group, 7 gamma group, 1200 mesh-points