Neutronics study of ITER shielding mock-up

A concept of "wet"-type (stainless steel-water) radiation shielding mock-up was developed which meets the most important demands to ITER shielding experiments: up to 1 m thick imitator of the shield and 30 cm thick imitator of the coil, easy variations of the assembly composition and SS/H2O ratio, effective protection of measurements from background, possibility to perform measurements in every SS plate and in coil imitator, minimal distortions of neutronics characteristics in area of measurements following from proposed radial channels concept, easy servicing of the assembly. The measurements at the stand of neutron generator SNEG-13 of the reaction rates: F-19(n,2n), Al-27(n,alpha), Fe-56(n,p), Ni-58(n,p), 58Ni(n,2n) at different locations inside the mock-up were carried out. The 3-D neutronics analysis of experiments was performed by MCNP-4A code with the data based on FENDL-1 library. From a comparison of measurements and calculations a general conclusion was drawn that neutron flux is well (within 10-15% of discrepancy) reproduced by calculation with FENDL data.