Neutronic simulation of the seventh irradiation experiment at the Swiss spallation neutron source

The SINQ Target Irradiation Program (STIP) is one of the important research projects performed at the Paul Scherrer Institute (PSI). The seventh experiment of the SINQ Target Irradiation Program (STIP-VII) was conducted with SINQ Target 10 from 2013 to 2014 and the total proton charge received by the target was 11.7 Ah. A radiation damage assessment was performed using MCNPX to predict the key radiation damage productions of displacement, helium and hydrogen for six materials, 9Cr-1Mo steel, Zry-2, Al, SiC, Ta and W, placed in different specimen rods. The incident proton source term for the assessment was produced with a gamma mapping measurement performed on the proton beam entrance window. The fluences of protons and neutrons as well as the energy deposition in the SINQ Target 10 were calculated. At an average proton beam current of 1.45 mA, the peak proton and neutron fluxes are 2.28 × 10¹⁴p/cm²/s and 5.60 × 10¹⁴n/cm²/s, respectively. The maximum irradiation dose and helium productions for steel specimens are 26.5 dpa and 2240 appm, respectively.