医用加速器场所中子和感生γ光子剂量当量的计算分析  

Dose equivalent of neutron and induced gamma rays near a medical accelerator

作　　者：陈宜正 李君利[1] 邱睿[1] 武祯[1] 康玺[2] 

机构地区：[1]清华大学工程物理系,粒子技术与辐射成像教育部重点实验室,北京100084 [2]南华大学核科学技术学院,衡阳421001

出　　处：《清华大学学报（自然科学版）》2016年第12期1284-1289,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家科技重大专项子课题(2013ZX06002001-007);国家自然科学基金资助项目(11275110,11375103)

摘　　要：医用高能加速器在广泛应用的同时,也存在着相关的辐射屏蔽问题,特别是迷宫内剂量的快速估算。该文对当前典型的迷宫内中子及感生γ光子剂量当量的计算方法进行了汇总,将其应用于多折迷宫的计算案例中,并与基于MCNP(Monte Carlo N-particle transport code)的Monte Carlo模拟值进行对比。结果表明:这些计算方法基本能够较为精确的估算迷道内不同点的中子和感生γ光子剂量当量,与Monte Carlo模拟值的偏差在1个数量级以内,但可能会低于模拟值。在实际应用中,可通过乘以安全系数以防止剂量低估。High energy accelerators are widely used in medicine, but the related radiation shielding calculations are difficult, especially for rapid assessments of the radiation dose in a maze. This study describes typical estimating methods for the dose equivalent of neutron and induced gamma rays in a maze, and calculates the dose equivalent in a multiple-bend maze. The results were compared with Monte Carlo simulations using the Monte Carlo N-particle transport code （MCNP）. The methods can accurately estimate the dose equivalent of the neutron and induced gamma rays in the maze, within an order of magnitude of the Monte Carlo simulation results, with underestimates in some cases. Therefore, a safety factor is suggested for practical applications.

关 键 词：剂量当量 迷宫 中子 感生γ光子 MONTE CARLO模拟 

分 类 号：TL72[核科学技术—辐射防护及环境保护]