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Updated: Jul 4, 2025

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使用MicroBooNE探测器在电子-正子和中性-引子最终状态中搜索重中性轻子
P Abratenko1, O Alterkait1, D Andrade Aldana2
1Tufts University, Medford, Massachusetts 02155, USA.
Physical review letters
|February 9, 2024
概括
在MicroBooNE中寻找重中性轻子 (HNLs),这些轻子分解成电子-正子或皮昂-光子对. 对HNL混合参数设置了新的限制,在关键质量范围内提供了最严格的约束.
科学领域:
- 粒子物理学 粒子物理学
- 实验性中微子物理实验
- 超越标准模型物理学的超越
背景情况:
- 重中性轻子 (HNL) 是标准模型之外的假设粒子.
- 寻找HNL可以揭示中微子质量和早期宇宙.
- 液体气时间投影室为检测罕见粒子衰变提供了独特的功能.
研究的目的:
- 进行首次搜索HNLs分解成nE^{+}e^{-}和nP^{0}最终状态.
- 使用MicroBooNE数据设置HNL混合参数的上限.
- 探测MeV范围内的HNL质量,并制约新的物理场景.
主要方法:
- 利用了MicroBooNE探测器的数据,这是一个液体气时间投影室.
- 分析了与费尔米实验室的NuMI中微子束同步收集的数据.
- 在目标曝光时,在7.01×10^{20}个质子内寻找特定的衰变特征 (νe^{+}e^{-}和νπ^{0}).
主要成果:
- 对于10-150 MeV (νe^{+}e^{-}通道) 和150-245 MeV (νπ^{0}通道) 之间的HNL质量,在%%的信心水平上确定了上限.
- 在35-175 MeV的质量范围内实现HNL混合的最严格的约束.
- 为 νπ^{0} 衰变通道提供了第一个直接搜索约束.
结论:
- MicroBooNE实验对沉重中性轻质子的存在提出了重要的新限制.
- 这些结果缩小了HNL的参数空间,并激励了进一步的搜索.
- 这项搜索证明了液体气时间投影室在探索标准模型物理之外的潜力.
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