放射源探测效率的动态刻度方法  

Dynamic calibration method for detection efficiency of radioactive source

作　　者：田自宁[1] 欧阳晓平[1] 韩斌[1] 陈伟[1] 苏川英[1] 刘文彪[1] 田言杰[1] 冯天成[1] 

机构地区：[1]西北核技术研究所,西安710024

出　　处：《强激光与粒子束》2016年第10期151-154,共4页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(11405134)

摘　　要：利用^(133)Ba面源和^(137) Cs点源匀速下降,成功刻度了^(133) Xe气体体源的探测效率和^(137) Cs线源的探测效率;利用^(133)Ba面源和^(137) Cs点源非匀速下降,成功刻度了非均匀分布的^(133) Xe气体体源的探测效率和^(137) Cs线源的探测效率。结果表明:匀速下降情况下,尺寸为ф46.8mm×20mm和ф63.5mm×20mm放射性^(133) Xe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。It is difficult to produce the radioactive standard gas source such as 133 Xe, which makes the calibration of yspectrometers difficult. The uniform falling velocities of the 133 Ba disk source and 137 Cs point source were used to calibrate the detection efficiency of 133 Xe 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 Ф46.8 mm× 20 mm sample） and 0. 143 （for 463.5 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.

关 键 词：探测效率 非均匀分布 动态刻度 气体源 蒙卡模拟 

分 类 号：TL814[核科学技术—核技术及应用]