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^{205}Tl^{81+}离子的边界状态β衰变和LOREX项目
R S Sidhu1,2,3, G Leckenby4,5, R J Chen2,3,6
1School of Physics and Astronomy, <a href="https://ror.org/01nrxwf90">The University of Edinburgh</a>, EH9 3FD Edinburgh, United Kingdom.
Physical review letters
|December 23, 2024
概括
研究人员测量了有离子的-205离子的边界状态β衰变. 比预期更长的半衰期挑战了探测太阳中微子的洛兰实验 (LOREX) 的可行性.
科学领域:
- 核物理 核物理 核物理
- 粒子天体物理学 粒子天体物理学
- 地质化学 地质化学
背景情况:
- 稳定的-205 (Tl) 离子拥有捕获电子中微子 (νe) 的最低能量值,这使得它们对太阳中微子检测至关重要.
- 拟议的洛兰石实验 (LOREX) 旨在使用天然洛兰石矿石测量长期太阳中性子流.
- 确定电子中性子捕获截面需要精确地了解Tl-205基体和Pb-205.5激发状态之间的弱过渡强度.
研究的目的:
- 实验性地确定Tl-205基态和Pb-205第一个2.3 keV激发状态之间的弱过渡的强度.
- 测量完全电离的TL-205 (Tl-205^81+) 离子的边界状态β衰变 (βb) 的半衰期,这是LOREX实验的一个关键参数.
- 根据测量的衰变特性,评估LOREX实验的可行性.
主要方法:
- 使用GSI,达尔姆施塔特的实验储存环 (ESR) 进行精确的测量.
- 对完全电离的TL-205^81+离子进行测量,以研究边界状态β衰变 (βb).
- 测量了TL-205^81+βb衰变的半衰期.
主要成果:
- 测量Tl-205^81+βb衰变的半衰期为291天 (不确定性为+33/-27天).
- 这种测量半衰期比理论模型先前预测的要长得多.
- 延长的半衰期意味着LOREX实验的信号噪声比减少.
结论:
- 对Tl-205^81+βb衰变半衰期的实验性确定为中微子物理学提供了关键数据.
- 测量的半衰期挑战了Lorandite实验 (LOREX) 的原始可行性预测.
- 可能需要进一步的研究来完善太阳中微子检测策略或探索替代方法.
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