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Updated: Jun 23, 2025

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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
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确定157 Tb 的活动和核衰变数据
Jonathan Riffaud1, Karsten Kossert1, Marcell Péter Takács1
1Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116, Braunschweig, Germany.
概括
本研究详细介绍了对-157 (157Tb) 衰变性能的精确测量. 先进的技术为157Tb产生了精确的排放率和电子捕获概率,这对于核数据应用至关重要.
科学领域:
- 核物理 核物理 核物理
- 放射化学 放射化学是指辐射化学.
- 原子物理 原子物理
背景情况:
- -157 (157Tb) 是一个与核应用相关的放射性同位素.
- 对157Tb的精确衰变数据对于各种科学领域至关重要.
- 以前的测量可能缺乏足够的精度或同位素纯度.
研究的目的:
- 为了放射化学提取和同位素净化-157 (157Tb).
- 准确确定157Tb的光子发射率和活动度.
- 精确测量电子捕获概率,并推导出157Tb的核特性.
主要方法:
- 从目标中进行放射化学提取.
- 在RISIKO质量分离器中使用激光共振电离的同位素净化.
- 高精度马射线光谱和液体闪计数 (TDCR, 4π(X,e) ((LS) - ((X,γ) ((CeBr3) 巧合计数).
主要成果:
- 对KX射线和马射线的发射强度分别确定为16.05 (%) 和0.0064 (%) 的分别.
- K电子被捕获到基本状态的概率为17.16~35% .
- 电子捕获分支到激发水平和基本状态的概率分别为0.084 ((4)%) 和99.916 ((4)%).
结论:
- 已经确定了-157 (157Tb) 的精确衰变数据.
- 获得的数据提高了核数据库的准确性.
- 这项工作为涉及157Tb的进一步研究提供了基础.
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