分段γ扫描装置校准用桶状标准源的设计  

Design of reference radioactive source of waste drum used in calibration of segmented gamma scan device

作　　者：徐利军[1,2] 叶宏生[1,2] 张卫东[1] 林敏[1,2] 肖雪夫[1,2] 陈细林[1] 郭晓清[1] 夏文[1] 陈义珍[1] 陈克胜[1] 

机构地区：[1]中国原子能科学研究院,北京102413 [2]计量与校准技术重点实验室,北京102413

出　　处：《核技术》2015年第5期67-73,共7页Nuclear Techniques

摘　　要：放射性废物桶分段γ扫描(Segmented Gamma Scanning,SGS)测量装置结构复杂,其测量对象即废物桶自身的放射性物质的分布、组成、活度范围以及堆积密度等差别较大,若对每类样品单独进行效率刻度,通常需要多个不同组成和体积庞大的刻度源,从而花费大量的时间和费用。通过对SGS装置的测量方法的研究,设计出以线状源法为核心的放射性废物桶标准源的基本模型,该模型由单个与废物桶相同高度的线状源插入废物桶中进行旋转测量形成,优点是放射性废物桶标准源内放射性核素与填充基质分开,结构灵活且安全性较高。通过实验测量结果和蒙特卡罗模拟的结果进行比较,验证其用于量值传递的可行性。Background： Segmented Gamma Scanning （SGS） device for radioactive waste barrel has complex structure and many kinds of measurement objects different in their constitution, distribution, range of radioactivity, bulk density, etc. Purpose： If the device for each sample was individually scaled, usually multiple different compositions and cumbersome calibration sources were required, which would cost a lot of time and money. So a reference source with appropriate design is required at first. Methods： Based on the study of calibration methods and Monte Carlo （MC） calculations for waste drums scanning devices, the basic model of reference source for radioactive waste barrels was established. Results： Reference source is composed of a waste barrel rotating in measurement and a linear source which inserted in it and the same height as the barrel. It is the advantage that radioactive material is separated from filling matrix in the barrel and of flexible structure as well as high security. Conclusion： The experimental measurements and MC simulation results are in great agreement especially in high energy point above 344.3 keV. It proves that the reference source can be used in value transfer for SGS devices.

关 键 词：废物桶 分段γ扫描装置 校准 标准源 

分 类 号：TL84[核科学技术—核技术及应用]