The application of “Helios” supercomputer in radiation safety studies for the IFMIF

The HELIOS supercomputer system at International Fusion Energy Research Centre, Aomori, Japan has been extensively utilized in radiation safety studies for the International Fusion Materials Irradiation Facility (IFMIF). This paper is focusing on the neutronic analysis to support the layout of the high energy beam transport (HEBT) section of IFMIF. The McDeLicious-11 Monte Carlo code, which is an enhancement to MCNP5, was utilized in order to simulate the neutron generation in the IFMIF lithium target through d-Li(d,xn) reactions and the R2Smesh approach was utilized to evaluate the ambient dose distribution after shutdown. The necessary thickness of the biological shielding and additional local shielding for the HEBT section has been evaluated. The accessibility of HEBT rooms and a necessary cooling time is discussed based on the result of shutdown dose analysis.