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从CUPID-Mo实验中测量了Mo的2νββ衰变速率和光谱形状
C Augier1, A S Barabash2, F Bellini3,4
1Univ Lyon, Université Lyon 1, CNRS/IN2P3, IP2I-Lyon, F-69622 Villeurbanne, France.
Physical review letters
|November 5, 2023
概括
在CUPID-Mo实验精确测量了两个中子双β衰变 (2νββ) 半衰期的-100. 这项研究还提供了对核结构和超越标准模型物理学的新见解.
科学领域:
- 核物理 核物理 核物理
- 粒子物理学 粒子物理学
- 超越标准模型物理学的超越
背景情况:
- 无中子双β衰变 (0νββ) 寻找超出标准模型的物理学.
- 两个中微子双β衰变 (2νββ) 是标准模型过程,为0νββ实验提供了基准.
- -100 (100Mo) 是双β衰变研究中的关键同位素.
研究的目的:
- 精确测量100Mo的2νββ衰变半衰期到100Ru的基本状态.
- 为了限制2νββ衰变的光谱形状的更高阶校正.
- 为了提取核结构信息和有效的轴向向量合常数.
主要方法:
- 使用CUPID-Mo实验设置检测2νββ衰变事件.
- 分析了100Mo衰变产品的能量光谱.
- 应用理论模型来解释光谱形状测量.
主要成果:
- 测量了100Mo的2νββ衰变半衰期为 (7.07±0.02±0.11) ×1018年,精度为1.6%.
- 报告了对形状因子 ξ3,1 = 0.45±0.03±0.05.5 的新型测量.
- 从光谱形状研究中提取有效轴向量合常数的第一个值.
结论:
- 取得的精度代表了迄今为止对100Mo最准确的2νββ衰变速率测量.
- 光谱形状约束提供了有价值的核结构信息,有助于解释0νββ衰变的搜索.
- 这项工作有助于理解超越标准模型的基本对称性和物理.
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