有效探测面积大于1000 cm^2的正比计数器测量系统性能测试  

Test of Proportional Counter System with Effective Detective Area Larger than 1000 cm^2

作　　者：林敏[1] 叶宏生[1] 徐利军[1] 陈克胜[1] 陈义珍[1] 夏文[1] 张卫东[1] 姚艳玲[1] 汪建清[1] 姚顺和[1] 李明[1] 

机构地区：[1]中国原子能科学研究院计量与校准技术重点实验室,北京102413

出　　处：《原子能科学技术》2016年第4期713-719,共7页Atomic Energy Science and Technology

摘　　要：为对自制的活性面积高达1 000cm^2的大面积源进行表面发射率定值,同时作为现有2πα、2πβ表面发射率标准装置能力的扩充,研制了一套内置式大面积2π多丝正比计数器测量系统,并利用活性区直径为8mm的^(241) Am点源及活性区面积为10cm×15cm的大面积^(241) Am和^(90)Sr-^(90) Y源对其进行计量学性能测试。结果表明:计数器内计数响应均匀性优于±0.4%,有效探测面积达1 400cm^2;所得241 Am源高压坪曲线的坪长为1 400V,坪斜为0.27%/100V,坪区内计数变化为0.87%;90Sr-90 Y源高压坪曲线的坪长为300V,坪斜为0.75%/100V,坪区内计数变化为0.80%;10次测量重复性好于0.4%,8h内短期稳定性好于0.3%,1a内长期稳定性好于0.8%。In order to determine the emission rate of the large-area source whose active area is up to 1 000cm^2,and to expend current standard ability of 2πα,2πβemission rate,a suit of large-area 2π multi-wire proportional counter system was established.The test about the characteristics of the whole system was carried out using both point source with active diameter of 8 mm and large-area source with active size of 10cm×15cm in this paper.The results show that the effective detective area is about 1 400cm^2 with homogeneity of counts of better than ±0.4%.The high-voltage plateau of ^241 Am source is about 1 400 V with a slope of 0.27%/100 V and variation coefficient of0.87%,while the high-voltage plateau of ^90Sr-^90Y source is about 300 V with a slope of0.75%/100 Vand variation coefficient of 0.80%.The repeatability of 10 measurements is better than 0.4%.Short term stability within 8his better than 0.3%,while long term stability within one year is better than 0.8%.

关 键 词：大面积多丝正比计数器 ^241Am源 ^90Sr-^90Y源 有效探测面积 高压坪曲线 重复性 稳定性 

分 类 号：TL81[核科学技术—核技术及应用]