超额允许的双重魔力核的Gamow-Teller衰变 100Snn
C B Hinke1, M Böhmer, P Boutachkov
1Physik Department E12, Technische Universität München, D-85748 Garching, Germany.
Nature
|June 23, 2012
概括
研究人员测量了最重的双重魔法核,锡-100.的衰变. 这项研究揭示了允许的核β衰变中最大的Gamow-Teller强度,证实了它的超允许性质.
科学领域:
- 核物理 核物理 核物理
- 原子结构 原子结构
- 量子力学就是量子力学.
背景情况:
- 原子核表现出与"神奇数"相关的外结构,由中子 (质子和中子) 在平均电位内的相互作用产生的.
- 贝塔加衰变涉及质子转变为中子,发射一个正子-中子对. 过渡被归类为Gamow-Teller或费米基于发射的粒子旋转.
研究的目的:
- 为了研究-100 (100Sn) 的β-衰变特性,这是具有相同质子中子比率的最庞大的双重神奇核.
- 测量100Sn的半衰期和衰变能量,以了解其衰变特征.
主要方法:
- 实验测量了100Sn的半衰期和衰变能量.
- 对100Snββ衰变中的Gamow-Teller过渡强度分布的分析.
主要成果:
- 确定了100Sn.β衰变的半衰期和衰变能量.
- 由于大量的衰变能量,观察到衰变强度的很大一部分.
- 在允许的核β衰变中测量了迄今为止最大的Gamow-Teller强度,将其确定为"超低"过渡.
结论:
- 100Sn的β衰变表现出一个超级允许的Gamow-Teller过渡,具有前所未有的强度.
- 现代的大规模外模型计算准确地复制了子核,-100 (100In) 中观察到的高强度和低状态.
- 这一发现为完善核结构模型和理解基本核过程提供了关键数据.
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