基于β衰变能谱测量探索确定137Cs衰变分支比的方法A METHOD FOR MEASURING THE BRANCHING RATIO OF 137Cs DECAYS BASED ON THE MEASUREMENT OF ENERGY SPECTRUM OF BETA-DECAY
李冉,张泽涛,秦雨浩,任赞,张高龙
摘要(Abstract):
文章用Si(Li)漂移探测器测量了~(137)Cs的β衰变能谱和内转换电子能谱,对高能区β能谱进行了库里厄图处理,得到~(137)Cs发生两种β衰变,分别到达~(137)Ba的基态3/2~+和激发态11/2~-的衰变分支比分别为(4.4±0.9)%和(95.6±0.9)%,该结果在统计误差的置信区间范围内。高能β射线的最大能量为(1022±274)keV,该结果同样在置信区间内,验证了本文采取的方法是正确的。由此绘制出~(137)Cs完整的衰变纲图,证明了测量β衰变能谱和内转换电子能谱的实验方法与理论基础的实用性。
关键词(KeyWords): β衰变;库里厄图;衰变纲图
基金项目(Foundation):
作者(Author): 李冉,张泽涛,秦雨浩,任赞,张高龙
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