Gamma radiation calculations and gamma blocker design for the high-energy beam transport region of the European Spallation Source

Abstract The purpose of this paper is to present the Monte-Carlo calculations performed design a special element called gamma blocker (GB), necessary stop radiation in Accelerator-to-Target (A2T) section European Spallation Source (ESS) linac. Very high levels emitted backward from activated target through beam pipe could effectively block any human intervention close transport system. residual dose rate linac tunnel was calculated without and with different GBs as function time. final GB material dimensions are proposed.