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在b→sl^{+}l^{-}衰变中测试莱普顿普遍性的测试
R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3
1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.
Physical review letters
|August 18, 2023
概括
这项研究测试了B介质子衰变中的电子普遍性,发现结果与标准模型一致. 该研究使用LHCb数据分析了罕见的B介质子衰变,为基本粒子物理学提供了新的见解.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 量子色态动力学 量子色态动力学
背景情况:
- 勒普顿普遍性是标准模型的一个关键预测,它指出像子和电子这样的基本粒子在某些相互作用中应该表现相同.
- 在B质中子衰变中偏离勒普顿普遍性可能表明超越标准模型的新物理学存在.
- 以前的实验已经暗示了潜在的差异,激励了进一步精确的测量.
研究的目的:
- 在B+→K+l+l−和B0→K*0l+l−衰变中进行第一个电子普遍性的同时测试.
- 测量在两个不同的范围的dielepton不变质量平方 (q2) 的lepton普遍性.
- 将实验结果与标准模型预测进行比较,以寻找新的物理现象.
主要方法:
- 利用了由LHCb探测器在2011年至2018年期间收集的质子-质子碰撞数据.
- 分析了相当于9 fb-1.1的集成亮度的大数据集.
- 对指定的B介质子衰变进行了分支比和角度可观测的精确测量.
主要成果:
- 介绍了四个勒普顿普遍性测量,每个测量都是其 q2 间隔的新,或者是对以前的 LHCb 结果的改进.
- 在涉及子和电子的衰变速率测量比率之间观察到的一致性.
- 所有测量结果都与标准模型预测在实验不确定性范围内兼容.
结论:
- 在这些B介质子衰变中,第一个电子普遍性的同时测试显示与标准模型一致.
- 在这项分析中,没有发现超出标准模型的新物理学的证据.
- 这些精确的测量有助于持续的努力,以高精度的数据从味道物理测试标准模型.
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