HIMM治疗室的辐射屏蔽设计

Radiation Shielding Design for Treatment Room of HIMM

摘要: 为了保证医用重离子加速器（HIMM）运行时的辐射安全，利用FLUKA计算了治疗时产生的瞬发中子源项，并对次级中子、γ辐射对屏蔽的影响进行了分析。用半经验公式及FLUKA计算了屏蔽厚度，给出了HIMM治疗室的屏蔽设计。在HIMM最大负载运行时，测量了屏蔽外中子剂量率，测量结果与模拟计算结果相符合。结果表明，本文选用的屏蔽设计方法是合理的，HIMM治疗室屏蔽设计方案满足国家标准要求。

Abstract: To guarantee the radiation safety of heavy ion medical machine (HIMM) during operation, the prompt neutron source term was calculated with the FLUKA code, and the effects of secondary neutron and gamma radiation on shielding were analyzed. The semi-empirical formula and FLUKA code were adopted to calculate the shielding thickness, and the shielding design of HIMM treatment room was given. At the condition of full power operation of HIMM, the measured neutron dose rate is in agreement with the simulation result. The results indicate that the calculation method is reasonable, and the result is in accordance with the requirements of the national standard.