Novosibirsk GDT-NS fusion material irradiation facility: Neutronic characteristics and potentialities

The paper briefly recalls the results of previously reported numerical stud ies on the feasibility of protective neutron shielding of the vital parts o f the Fusion Material Irradiation Facility (FMIF) Neutron Source (NS) based on the Novosibirsk Gas Dynamic Trap (GDT). The work stresses the neutronic potentialities of the facility. This mirror-type machine is designed to pr oduce 10(18) D-T neutrons/s over IO years (3x10(26) neutrons). Simulations use the 3DAMC-VINIA Monte Carlo code with its drizzle-shower splitting tech nique and two-step cascade (bilinear functional) treatment, ENDF/B6 files, and an engineering design model that precisely reproduces critical parts of the facility. The proposed shielding ensures survival of the facility, as per project tolerances, with further shield reduction and optimization poss ible. Present partial shield reductions around the plasma column consent 2. 5m(3) of irradiation space,with 0.06m(3) at 0.3x10(14) thermonuclear uncoll ided n(DT)-neutrons/cm(2)s (0.5 MW/m(2)) and 0.7x10(14) collided ones, axia l damage gradients less than or equal to 1%/cm over 7.8m, and similar to 30 dpa in Fe-type materials at end of life.