基于Monte-Carlo模拟和峰形拟合的CdZnTe探测器G(E)函数简便计算方法研究

提出了一种简便的CdZnTe探测器能谱-剂量转换函数(G(E)函数)的计算方法。峰形拟合函数被用于表征CdZnTe探测器对γ射线的低能拖尾,峰形拟合函数的参数通过实验测量获取,并通过拟合得到其随能量变化的关系。Monte-Carlo模拟计算得到的探测器理想沉积谱,经峰形拟合函数卷积得到了修正的模拟能谱,修正的模拟能谱与实际测量能谱吻合较好。基于修正的模拟能谱计算得到了CdZnTe探测器的G(E)函数。标准辐射场中的实验结果表明,用G(E)函数加权积分计算的周围剂量当量率与约定真值基本一致。

Study on Simple G(E) Function Calculation Method of CdZnTe Detector Based on Monte-Carlo Method and Peak Shape Fitting

A new simple calculation method was proposed to calculate the spectrum to dose function (G(E) function) of CdZnTe detector .The peak shape fitting function was used to feature the tailing of CdZnTe detector spectrum . The relationship between variable of peak shape fitting function and energy was derived from experiments .The Monte‐Carlo method was used to simulate the ideal spectrum of CdZnTe detector .By convoluting the ideal spectrum and peak shape fitting function ,the refined spectrum was derived ,and it is in agreement with measurement spectrum .G(E) function of CdZnTe detector was calculated based on refined spectrum from simulation . The experiment result show s that ambient dose equivalent rate calculated via G (E) function is in good agreement with conventional real value of standard radiation field .