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寻找奇特的希格斯玻色子 衰变 H→AA→4γ 与包含两个合并的二光子在sqrt[s]=13 TeV的质子对质子碰撞中的事件
A Tumasyan1, W Adam2, J W Andrejkovic2
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|September 22, 2023
概括
这项研究寻找了奇特的希格斯玻色子分解成两个低质量粒子 (A),这些粒子分解成光子. 没有发现证据,限制了希格斯玻色子 (H) 衰变到四个光子的限制.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 标准模型扩展 标准模型扩展
背景情况:
- 粒子物理学的标准模型 (SM) 描述了基本粒子和力.
- 在SM之外的奇特希格斯玻色子衰变被积极寻找.
- 低质量级粒子 (A) 衰变为光子 (A→γγ) 是假设的扩展.
研究的目的:
- 为了进行第一个对异国情调的希格斯玻色子的直接搜索,H→AA衰变,其中A是一个低质量的自旋零粒子.
- 为了研究A→γγ衰变,A被重建为一个单一的光子样物体.
- 在H→AA→4γ的分支分数上设置排除限制.
主要方法:
- 分析CMS实验在13TeV的质量中心能量下收集的质子对质子碰撞数据.
- 使用了136fb-1的集成亮度.
- 搜索两个与H→AA→4γ衰变特征一致的光子样物体发生的事件.
主要成果:
- 没有观察到超过预期背景的事件显著超出.
- 分支分数 B ((H→AA→4γ) 的上限设置为 95% 的置信水平.
- 极限范围从 (0.9-3.3) ×10−3为A质量在0.1和1.2GeV之间.
结论:
- 寻找异国情调的希格斯玻色子衰变H→AA→4γ并没有为此类过程提供证据.
- 结果为涉及低质量标量粒子的新物理模型的参数空间提供了严格的约束.
- 这项研究有助于在大型强子对撞机 (LHC) 进行超越标准模型的探测物理学的持续努力.
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