放射性活度检测系统设计

Design of Radioactivity Detection System Based on Spectrum Stabilization Circuit

针对目前放射性检测仪的现状,通过对γ射线进行能谱分析,利用放射性脉冲检测电路的刻度能量和道数关系计算出放射性元素的全能峰净面积、效率刻度和活度等参数,设计一种放射性活度检测系统.实验结果表明:在24h内重复测量同一样品的核素活度,2次测量的相对误差小于6%,在-5～+40℃温度范围内,谱漂的最大值不超过±2道,且测量的总不确定度小于20%;系统性能稳定,误差较小,方便现场放射性元素的检测.

Aiming at the current domestic situation of radioactive detectors,we analyzed the energy spectrum of γ-ray and calculated the full peak net area,efficiency calibration,activity of the radioactive detector according to the relationship between energy and channel number of radioactive pulse detection circuit.Within 24 h of repeated measurements in the same product nuclide activity,two measurements of the relative error is less than 6% in a temperature range of-5—＋40 ℃,the maximum of the spectrum drift does not exceed ±2 and the measurement of the total uncertainty is less than 20%.The results show that the system is stable with small error and is convenient for the on-site detection of radioactive elements.