Preliminary Shielding For The CSNS Target Station Based On Two-dimensional Discrete Ordinates Method

The construction of China Spallation Neutron Source (CSNS) has been initiated at Dongguan, Guangdong, China. A detailed radiation transport analysis of the target station is important for the construction of CSNS. Neutron transport calculation mainly affected by cross section library and code. A high energy multi-group library named HEST1.0 is developed based on ENDF/B-VII.0 using NJOY code. A detail of the verification of the multi-group library by several shielding benchmark devices were completed, especially for high energy neutron data. Discrete ordinates (SN) method is a widely used method in the shielding design due to its powerful capability to treat deep-penetration shielding problem. Based on the design of CSNS target station neutron beam extraction pipes and biological shielding monolith, shielding efficiency is evaluated of the different design model using the two-dimensional discrete ordinates transport code DORT. Two-dimensional dose field distribution and the axial distribution were calculated. Meanwhile, an optimal shielding model was obtained from the calculation. The model ensured that the received doses of the hall staff members below the required standard limit.