ORTEC GEM70P4-95 P型高纯锗γ谱仪的标定

Calibration of the ORTEC P type Ge γ-ray spectrometer

高纯锗γ谱仪是释光/ESR测年中环境剂量率测量的重要方法之一,其标定(能量和效率刻度)是一项重要的基础性工作。利用中国剂量科学研究院提供的U/Th/Ra/K等标样,标定了本实验室的ORTECGEM70P4-95 P型高纯锗γ谱仪。选择不同类型的样品,进行了测量时间长短对实验结果影响的实验,结果显示在测量时间达到8 h即可满足要求;另外同时进行了高纯锗γ谱仪与ICP-MS比对测量,两种方法测量结果在误差范围内完全一致,说明标定结果是可靠和准确的,此仪器可以广泛应用于释光/ESR测年环境剂量率的测量中。

Ge γ-ray spectrometer is an important tool for determining potassium,uranium and thorium contents in sediments.The results depend on accuracy of the calibration and the extent to which the measuring conditions resemble those adopted during calibration.Our ORTEC GEM70 P4-95 P type Ge γ-ray spectrometer was calibrated by measuring K,Ra,Th and U standards from Ionizing Radiation Division National Institute of Metrology.Different type samples were analyzed by both ICP-MASS and the Ge γ-ray spectrometer.The results show that 8 hours measured time are enough and the calibration is accurate.