强激光与粒子束, 2016, 28 (10): 106002, 网络出版: 2016-09-14
放射源探测效率的动态刻度方法
Dynamic calibration method for detection efficiency of radioactive source
探测效率 非均匀分布 动态刻度 气体源 蒙卡模拟 detection efficiency heterogeneous distribution dynamic calibration gas source Monte Carlo simulation
摘要
利用133Ba面源和137Cs点源匀速下降,成功刻度了133Xe气体体源的探测效率和137Cs线源的探测效率; 利用133Ba面源和137Cs点源非匀速下降,成功刻度了非均匀分布的133Xe气体体源的探测效率和137Cs线源的探测效率。结果表明:匀速下降情况下,尺寸为46.8 mm×20 mm和63.5 mm×20 mm放射性133Xe气体体源的探测效率分别为0.155 和0.143,标准不确定度为8.4%(包含因子k=2 )。非均匀分布的体源效率和均匀分布的体源效率两者偏差在14%,线源的偏差在23%,可见由非均匀性引起的误差必须进行校正。
Abstract
It is difficult to produce the radioactive standard gas source such as 133Xe, which makes the calibration of γ spectrometers difficult. The uniform falling velocities of the 133Ba disk source and 137Cs point source were used to calibrate the detection efficiency of 133Xe volume source and 137Cs linear source. The non-uniform falling velocities of 133Ba disk source and 137Cs point source were used to calibrate the detection efficiency of heterogeneous 133Xe volume source and heterogeneous 137Cs linear source. The results show that the detection efficiencies of 133Xe were 0.155 (for 46.8 mm×20 mm sample) and 0.143 (for 635 mm×20 mm sample) respectively, obtained for the uniform falling velocity of the source, and the uncertainty was 8.4% (k=2). The deviation between the efficiency of the heterogeneously distributed volume source and the efficiency of uniform volume source in 14%, and 23% for linear sources. Therefore, the deviation caused by heterogeneity must be corrected.
田自宁, 欧阳晓平, 韩斌, 陈伟, 苏川英, 刘文彪, 田言杰, 冯天成. 放射源探测效率的动态刻度方法[J]. 强激光与粒子束, 2016, 28(10): 106002. Tian Zining, Ouyang Xiaoping, Han Bin, Chen Wei, Su Chuanying, Liu Wenbiao, Tian Yanjie, Feng Tiancheng. Dynamic calibration method for detection efficiency of radioactive source[J]. High Power Laser and Particle Beams, 2016, 28(10): 106002.