Transmutation of Hydrogen and Helium Atoms in Neutron Irradiated Iron and Tungsten

Abstract

Numerical calculations of the hydrogen (H) and helium (He) transmutation atoms production in iron (Fe) and tungsten (W) irradiated by fusion 14.1 MeV neutrons were carried out by using FLUKA and MCNPX codes. This study has demonstrated good agreement between two MC codes for transmutation production ratio. H and He atom production depends on the target depths. The corresponding accumulation of H and He atoms in 16 cm Fe target for full power year (fpy) decreases by 56% atomic parts per million (appm/fpy) in comparison with the initial concentrations. The production of H in Fe depth 16 cm for fpy to 1 MW/m² by FLUKA and MCNPX is about 124.73 appm/fpy, while the amount of He reaches 28.56 appm/fpy. In tungsten for depth 16 cm hydrogen production for fpy 1 MW/m² is 1.40 appm/fpy (FLUKA) and 1.46 appm/fpy (MCNPX), while for He production it is 0.37 appm/fpy by FLUKA and 0.40 appm/fpy by MCNPX.