摘要
220 Rn的准确测量是天然辐射照射剂量评价体系中的重要研究内容之一。普通闪烁室体积较大,对222 Rn、220 Rn及其子体衰变产生的不同能量的高能α粒子具有不同的探测效率。本文提出调低标准闪烁室内气压,使222 Rn衰变产生的能量最小的α粒子在闪烁室内的射程大于闪烁室内任意两点间最长距离,这样,低压闪烁室对222 Rn、220 Rn及其子体衰变产生的α粒子探测效率相同。利用标准氡室可得到低压闪烁室对α粒子探测效率,进而可使用低压闪烁室对220 Rn浓度参考水平定值。
The accurate measurement of 220Rn is important for dosimetry evaluation of natural radiation exposure.The detection efficiencies of normal scintillation cell to different energy α particles decayed from 222Rn,220Rn and their daughters are different for the large volume of normal scintillation cell.It was proposed that the range of α particles with minimum energy decayed from 222Rn could be longer than the longest distance between any two points in the scintillation cell by reducing the air pressure of scintillation cell.Thus,the detection efficiencies of the low-pressure scintillation cell to α particles decayed from 222Rn,220Rn and their daughters are same.The detection efficiency of low-pressure scintillation cell to α particles can be obtained by standard radon chamber,and then the 220Rn concentration reference value can be determined by low-pressure scintillation cell.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2013年第7期1277-1280,共4页
Atomic Energy Science and Technology
基金
国家自然科学基金资助项目(11075049)
关键词
220Rn浓度参考水平
低压
闪烁室
220Rn concentration reference value
low-pressure
scintillation cell
