【摘要】 将小型4πβ流气式正比计数器置于大体积4πγNaI(Tl)探测器中,组成4πβ-4πγ符合装置,采用效率外推法测量了59Fe溶液的比活度,研究γ道探测效率很高时符合外推法活度测量准确度的改善情况。结果表明,γ道探测效率的提高,显著减少了活度测量的统计不确定度,有效地缩短效率外推全过程的时间,因此适用于较短寿命放射性核素活度的测量。更多还原

【Abstract】 4πβ4πγ coincidence system was built by putting a small 4πβ flow proportional counter into a large size 4πγ NaI(Tl) detector. In order to investigate the improving of the accuracy of activity by increasing of γ efficiency, the efficiency extrapolation method was applied to measure the specific activity of the 59Fe solution. The results indicate that increasing γ efficiency can obviously reduce the activity measurement uncertainty and reduce the time of efficiency extrapolation, so this method is fit for measuring the activity of short halflife nuclides.更多还原