Effects of irradiating the beam dump with the main electron beam of the superconducting linear accelerator PolFEL

Abstract The transport of both primary and secondary radiation in the beam dump was conducted using Monte Carlo analysis. The radiation leakage level through the shielding walls of the bunker of the superconducting, linear electron accelerator PolFEL during beam operation, as well as the radiation dose generated by radioactivity, and the activity level of the beam dump and soil after beam operation were examined. The analysis encompassed three main electron beams with energies of 72 MeV, 187 MeV, and 280 MeV, corresponding to the need to deposit in the beam dump 900.0 W, 935.1 W, and 1400.1 W of electron beam power, respectively. It was determined that 99.86%, 99.83%, and 99.81% of the primary electron beam power was deposited in the designed beam dump. It was determined that the radiation leakage level through the lateral walls of the bunker, outside which nonexposed workers may stay, should be <1.8 · 10 −4 μSv/h, 0.008(5) μSv/h, and 0.10(2) μSv/h, respectively. It was calculated that the radiation dose rate generated by radioactivity allows staying on the shielding plates above the beam dump no earlier than about a day after the end of the 30 days exposure period of the beam dump. The maximum activity level for the soil activity level at the most exposed location should be <0.008 Bq, 3.37(15) Bq, and 29.8(9) Bq for indicated above electron beam energies, respectively.