利用241 Am发射的59.54 keV平行γ射线束对宽能BEGe探测器晶体进行扫描测量，通过晶体端面垂直扫描确定晶体直径，通过晶体侧面垂直扫描确定晶体高度。利用厂家提供的参数以及扫描得到的晶体参数建立蒙特卡罗计算模型，再通过点源和体源的实验测量值对晶体前端面及侧面死层厚度进行表征调节，使其与实验值符合，从而获得最佳理论计算模型。结果表明，获得的参数正确可靠，其点源探测效率的理论计算结果与实验测量值在2％内符合。该方法极大改善了蒙特卡罗计算BEGe晶体探测效率的精度，可应用于探测器的效率刻度及环境放射性调查。%Based on BEGe γ spectrometer ,the scanning measurement was operated by parallel 59.54 keV γ-ray which was emitted by 241 Am . The crystal diameter was obtained by scanning perpendicular crystal front surface ,and the crystal height was obtained by scanning perpendicular crystal lateral surface . T he crystal parameters provided by manufacture and scanning were used to establish the Monte Carlo module . Based on the calibration results of the sources , the front and lateral dead layer thinknesses of BEGe were characterized .A good consistent result between Monte Carlo result and experiment value was finished by using character parameters ,and the best theory module was obtained . Viewing the result data , the parameters are valid and reliable .The Monte Carlo results are consistent with the experimental results of point source in 2% . Therefore , this method greatly improves the γ spectrum’ s metrical accuracy ,and it can be widely applied in detector efficiency calibration and environmental radioactive investigation .
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