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Updated: Jun 23, 2025

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组合搜索共振希格斯玻色子对生产使用pp碰撞在sqrt[s]=13TeV与ATLAS探测器的搜索
Physical review letters
|June 21, 2024
概括
研究人员使用ATLAS探测器数据寻找新的共振分解成希格斯玻色子对. 没有发现证据,并且对希格斯玻色子对生产的生产截面设置了上限.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 碰撞器物理学 碰撞器物理学
背景情况:
- 粒子物理学的标准模型 (SM) 描述了基本粒子和力.
- 寻找超越标准模型 (BSM) 的物理学对于理解宇宙至关重要.
- 希格斯玻色子对的产生为BSM物理学提供了一个独特的窗口.
研究的目的:
- 为了寻找一个新的标量共振分解成一对希格斯玻色子.
- 为了设定希格斯玻色子对生产截面的限制.
- 探测新的物理模型,包括I型二希格斯双重模型和最小超对称标准模型.
主要方法:
- 对三个衰变通道的综合分析:HH -> bb[over ̄]bb[over ̄],HH -> bb[over ̄]τ^{+}τ^{-},以及HH -> bb[over ̄]γγ.
- 使用了高达 139 fb^{-1} 的质子对质子碰撞数据在 sqrt[s]=13 TeV.
- 大强子对撞机 (LHC) 的ATLAS探测器收集的数据.
主要成果:
- 没有观察到高于预期的标准模型背景的显著超值.
- 对于希格斯玻色子对的生产截面,在95%的置信水平上设置了上限.
- 对横截面的观察 (预期) 极限范围从0.96 (1.2) fb到600 (390) fb,共振质量在251 GeV到5 TeV之间.
结论:
- 该研究限制了各种新物理模型的参数空间.
- 结果排除了I型两希格斯双重模型和最小超对称标准模型参数空间中的区域.
- 这种探索有助于对超越标准模型的物理学的持续探索.
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