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%.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2016年第4期713-719,共7页
Atomic Energy Science and Technology
