ratio of activity densities

Two calculational methods for analyzing the spectrum which measured by indoor low background multi-channels gamma-rays spectometer(Na(Tl)) to get the specific activity of 226Ra, 232Th and 40K of the sample are discussed, they are the spectrum analysis method and the characteristic energy peak method(inverse matrix method) respectively.

论述了以NaI(Tl)晶体为探测器的室内低本底多道γ射线能谱仪用于测量样品中226Ra、232Th和40K放射性比活度的两种计算方法———谱线分解法和特征能量峰法(逆矩阵法),并设计编制程序,分别采用这两种方法对样品谱线进行处理分析,将分析结果与高纯锗γ谱仪分析结果对比,两种方法分析同一样品的相对偏差均≤10%。