β表面污染现场测量技术研究

The study on field measurement technology of beta surface contamination

为了探索不同的影响因素对β表面污染测量效率的影响,本文主要利用CoMo170表面污染监测仪对60 Co平面源、^(204)Tl平面源及^(90)Sr-^(90)Y平面源进行测量,研究了能量响应、探测窗响应均匀性、测量间距、吸收效应、γ射线干扰以及反散射等因素对于表面活度响应值的影响规律,并进行了测量不确定度的评定。通过实验研究,得到各个因素对测量结果的准确度造成的影响,其中影响最大的因素主要是能量响应和γ射线干扰,实验测量最终不确定度评定结果表明,其相对合成标准不确定度约为46.71%。

In order to explore the influence of different influencing factors on the measurement efficiency of beta surface contamination,this paper mainly uses CoMo170 surface contamination monitor to measure the 60 Co plane source,the ^(204)Tl plane source and the ^(90)Sr-^(90)Y plane source,and studies the influence of energy response,detection window response uniformity,measurement spacing,absorption effect,gamma ray interference and back scattering on the surface activity response,and the measurement uncertainty is evaluated.Through experimental research,the influence on the accuracy of the measurement results is obtained.Among them,the most influential factors are energy response and gamma ray interference.The final uncertainty evaluation result of the experimental measurement shows that its relative synthetic standard uncertainty is approximately equal to 46.71%.