同时探测和底夸克Yukawa合使用tt[over ̄]H事件
A Hayrapetyan1, V Makarenko1, A Tumasyan1
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|January 26, 2026
概括
研究人员使用13 TeV的质子对质子碰撞数据,搜索希格斯玻色子衰变为魅力夸克与顶级夸克相关. 这项研究提供了迄今为止对希格斯 - 魅力尤卡瓦合的最严格的约束.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 标准模型物理学的标准模型.
背景情况:
- 粒子物理学的标准模型 (SM) 描述了基本粒子和力.
- 希格斯玻色子是SM中的一个关键粒子,负责质量.
- 了解希格斯玻色子与不同夸克的合对于测试SM至关重要.
研究的目的:
- 为了寻找希格斯玻色子罕见的衰变成一个魅力夸克-反夸克对 (H→cc[over ̄]).
- 测量希格斯玻色子衰变到底部夸克-反夸克对 (H→bb[over ̄]) 与顶部夸克-反夸克对 (tt[over ̄]H) 相结合.
- 为了限制希格斯魅力的尤卡瓦合修饰器 (κc).
主要方法:
- 对在sqrt[s]=13 TeV的质子对质子碰撞数据的分析,整合光度为138 fb−1.
- 利用先进的机器学习进行喷气风味识别和事件分类.
- 与H→bb[over ̄]和H→cc[over ̄]衰变同时测量tt[over ̄]H的产生.
主要成果:
- 对tt[over ̄]H(H→bb[over ̄]) 的观察到的事件率相对于SM预测是0.91_{-0.22}^{+0.26}.
- 在95%的置信级别下,设定了 σ(tt[over ̄]H) B(H→cc[over ̄]) 的上限为0.11 pb (观察) 和0.13 pb (预期).
- 结合先前的结果,观察到的95%置信区间为3.5,预期为2.7.
结论:
- 这项研究为希格斯-尤卡瓦合设定了迄今为止最严格的极限.
- 结果与标准模型预测一致.
- 这项搜索推动了我们对希格斯玻色子与轻夸克相互作用的理解.
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