医用加速器场所中子和感生γ光子剂量当量的计算分析

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清华大学辅仁网/2017-07-07

陈宜正¹, 李君利¹, 邱睿¹, 武祯¹, 康玺²

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

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

CHEN Yizheng¹, LI Junli¹, QIU Rui¹, WU Zhen¹, KANG Xi²

1. Key Laboratory of Particle and Radiation Imaging of Ministry of Education, Department of Engineering Physics, Tsinghua University, Beijing 100084, China;
2. School of Nuclear Science & Technology, University of South China, Hengyang 421001, China

摘要:

输出: BibTeX | EndNote (RIS)

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。

关键词 ：剂量当量,迷宫,中子,感生&gamma,光子,Monte Carlo模拟

Abstract：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.

Key words：dose equivalent maze neutron induced gamma ray Monte Carlo simulation

收稿日期: 2015-10-26 出版日期: 2016-12-20

ZTFLH:

TL72

通讯作者:邱睿,副教授,E-mail:quirui@tsinghua.edu.cnE-mail: quirui@tsinghua.edu.cn

引用本文:

陈宜正, 李君利, 邱睿, 武祯, 康玺. 医用加速器场所中子和感生γ光子剂量当量的计算分析[J]. 清华大学学报（自然科学版）, 2016, 56(12): 1284-1289.
CHEN Yizheng, LI Junli, QIU Rui, WU Zhen, KANG Xi. Dose equivalent of neutron and induced gamma rays near a medical accelerator. Journal of Tsinghua University(Science and Technology), 2016, 56(12): 1284-1289.

链接本文:

http://jst.tsinghuajournals.com/CN/10.16511/j.cnki.qhdxxb.2016.25.020或 http://jst.tsinghuajournals.com/CN/Y2016/V56/I12/1284

图表:

图1 多折迷宫结构图

图2 中子剂量当量计算值与MonteCarlo模拟值对比

图3 第一折迷道中子剂量当量计算值与蒙特卡罗模拟值对比

图4 第二折迷道中子剂量当量计算值与MonteCarlo模拟值对比

图5 第三折迷道中子剂量当量计算值与MonteCarlo模拟值对比

图6 感生γ光子剂量当量计算值与MonteCarlo模拟值对比

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