Shielding calculation for the CSNS target station

In this paper we firstly calculate the one-dimension shielding models to give the basic data for the Chinese Spallation Neutron Source (CSNS) target station. Then the three-dimensional shielding calculations have been performed for the detailed design of the CSNS target station. The gaps and void spaces in the CSNS target station are considered for precise estimation. We find that 4.8-meter-radius steel adding 1.2-meter-thick magnetite concrete can satisfy the shielding requirement in the horizontal direction. The dose rate on the top of the ceiling is a little higher than 2.5μSv/h due to streaming effect, which originates from the moderator transfer lines. A thin sandwich structure will be adopted for decreasing residual radioactivity dose rate on the altitude directions after considering the engineering cost and maintenance. All these calculations lie on the Monte Carlo simulation code MCNPX2.5.0.