title: Monte Carlo calculation of epithermal neutron resonance self-shielding factors in foils of different materials.
abstract: Epithermal neutron resonance self-shielding factors in foils of materials used as activation detectors or as targets for radionuclide production have been calculated using the MCNP code. Two irradiation conditions have been considered: (a) foils immersed into an isotropic neutron flux and (b) foils submitted to a collimated neutron beam. The self-shielding factors, Gres(t), for gold, indium, manganese and cobalt have been compared with available published values. The self-shielding factor depends on various physical and nuclear parameters. However, it is shown that for the isotropic case and for high absorber elements submitted to a collimated beam, a dimensionless variable could be adopted that describes the self-shielding factors of different materials by quasi "universal curves". Gres(t) for the collimated beam are always higher than those for the isotropic case.
authors.affiliation: Instituto Tecnológico e Nuclear, Estrada Nacional, Sacavém, Portugal. ifg@itn.pt
authors.forename: I F
authors.initials: IF
authors.lastname: Gonçalves
authors.forename: E
authors.initials: E
authors.lastname: Martinho
authors.forename: J
authors.initials: J
authors.lastname: Salgado
mesh_terms: D009010:Monte Carlo Method; D009502:Neutrons; D011835:Radiation Protection; D011837:Radiation-Protective Agents / Q000032:analysis
chemical_list: D011837:Radiation-Protective Agents