Neutron Flux and Activation Calculations for A High Current Deuteron Accelerator

Neutron analysis of the first Neutral Beam (NB) for the International Thermonuclear Experimental Reactor (ITER) was performed to provide the basis for the study of personnel safety during normal operation and maintenance. The first ITER NB is a 1 MeV negative deuterium ions accelerator. The daily average beam current is 13.3 A. To assess neutron transport in the ITER NB structure a mathematical model of the components geometry was implemented into MCNP (Monte Carlo N-Particle transport code system) computer code. The neutron source definition was outlined considering both D-D and T-D neutron production. FISPACT code was used to assess neutron activation in the material of the system components. Radioactive inventory and contact dose rate were assessed considering the potential operative scenarios.