摘要
通过对不同厚度样品的γ射线测量,得出波谱峰面积与样品厚度的关系,并通过相对测量和效率刻度测量方法,计算不同厚度样品在46.5、351.9、477.6、661.7 keV能量下的探测效率。探测效率随样品厚度的变化较大,不同厚度样品的4种探测效率最大值平均为最小值的2.6倍。实验结果显示:探测效率随样品厚度增加而逐渐减小,呈现对数关系。随着能量的增加,对数关系减弱,线性关系增强。
Detection efficiency of HPGe y spectrometer is an important performance and has a greater impact on radioactivity measurement results of soil samples. By measuring γ-rays from ^210Pb（46.5 keV）, ^214pb（351.9 keV）, ^7Be（477.6 keV） and ^137Cs（661.7 keV） in soil samples of 15-95 mm in thickness （solid angles of-100°- -60°）, the relationship were investigated between the sample thickness and the T-ray counts obtained by efficiency calibration or comparative measurements. The results showed that the detection efficiency decreases with increasing sample thicknesses, with the largest ratio （3.5） of maximum/minimum detection efficiency at 46.6 keV and the smallest （2.2） at 661.7 keV. The detection efficiency decrease at low energies was in a logarithm way, while at high energies the detection efficiency decreased linearly.
出处
《核技术》
CAS
CSCD
北大核心
2011年第9期683-688,共6页
Nuclear Techniques
基金
国家自然科学重点基金(41030751)
国家自然科学面上基金(40873071)
江苏省教育厅重大项目(09KJA170002)
江苏高校优势学科建设工程资助
关键词
高纯锗Γ谱仪
探测效率
样品厚度
HPGe γ spectrometer, Detection efficiency, Sample thickness
