应用蒙特卡罗方法确定NaI探测器的点源效率函数及其参数

Monte Carlo simulations of efficiency function of NaI detector and its parameters for point sources

为了探讨NaIγ探测器对点状γ射线源(以下简称“点源”)的探测效率与点源空间位置之间的关系,采用蒙特卡罗方法通用程序模拟计算了NaIγ探测器对空间不同位置处137Cs、60Co点源的探测效率。根据模拟计算结果,通过数值拟合方法,确定了NaI探测器对点源的探测效率函数及其参数。研究表明,应用蒙特卡罗模拟方法确定NaIγ探测器对于点源的探测效率函数及其参数是一种简便、有效的方法。

In order to study the relationship between the counting efficiency and the point source positions, a Monte Carlo code （MCNP4C） has been used to calculate the counting efficiency of NaI detector for the standard γ-ray point sources in different space positions. For the 137^Cs and 60^Co point sources, the counting efficiency function of the NaI detector and its parameters have been determined by fitting the calculated data. The results indicate that the Monte Carlo method is simple and effective in determining the counting efficiency function of NaI detector and its parameters for the γ-rav point sources.