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Setting Limits on Supersymmetry Using Simplified Models
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在pp中搜索光长寿命粒子 在sqrt[s]=13 TeV的碰撞中使用ATLAS内部探测器中的移位顶点
Physical review letters
|November 1, 2024
概括
这项研究使用来自大型强子对撞机的ATLAS数据搜索长寿命粒子 (LLPs). 没有发现任何显著的过量,这导致了希格斯玻色子和顶夸克衰变的新极限,涉及LLP和axion-like粒子.
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允许超出其预测的新现象.
- 长寿命粒子 (LLPs) 是假设的粒子,在衰变之前,它们可以行驶可检测的距离.
- 对LLP的搜索可以探测新的物理模型,包括那些涉及异国情调的希格斯玻色子衰变和axion-like粒子 (ALPs) 的模型.
研究的目的:
- 为了在ATLAS内部探测器中寻找长寿命粒子 (LLPs) 的电子衰变.
- 为了研究具有从异国情调的希格斯玻色子衰变中LLP对生产的基准模型.
- 探索与矢量玻色子和顶夸克衰变相关生成的长寿命轴状粒子 (ALP) 的模型.
主要方法:
- 分析了140fb^{-1}的质子对质子碰撞数据在13TeV的质量中心能量收集的ATLAS实验.
- 针对5至55GeV之间质量的LLP,这些LLP的色衰变.
- 使用复杂的背景估计技术来比较观察到的数据与理论预测.
主要成果:
- 在分析的数据中,没有发现超过预期背景的事件显著超出了预期的背景.
- 对希格斯玻色子与LLP对的分支比率设置了上限.
- 对用矢量玻色子生成的ALP的截面设定了上限,并首次对ALP和轻夸克的顶夸克分支率设定了上限.
结论:
- 搜索对预测长寿命粒子存在的模型提供了严格的约束.
- 结果排除了异国情调的希格斯玻色子衰变和axion-like粒子生成的某些参数空间.
- 这项研究通过限制新的粒子特性和相互作用,为正在进行的超越标准模型的物理学探索做出了贡献.
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