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寻找一个看不见的Z^{'}在一个最终状态与两个子和缺少的能量在贝尔II的搜索
Physical review letters
|June 24, 2023
概括
研究人员正在寻找一个新的Z.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 超越标准模型物理学的超越
背景情况:
- 粒子物理学的标准模型有局限性,需要扩展.
- LμLτ扩展预测了一个新的Z'玻色子与更重的子相互作用.
- 勒普顿风味普遍性违规是这种扩展的一个关键预测.
研究的目的:
- 为了寻找由LμLτ扩展预测的Z'玻色子.
- 为了研究电子-正电子碰撞中Z'玻色子的无形衰变.
- 为了限制Z'玻色子的特性和合强度.
主要方法:
- 利用了来自贝尔II实验的电子-正子碰撞数据 (79.7fb-1在10.58GeV).
- 搜索了过程e+e− → μ+μ−Z'与随后的隐形Z'衰变.
- 分析数据以超出标准模型背景预测的过量.
主要成果:
- 没有观察到可归因于Z'玻色子的事件显著过多.
- 确定了e+e− → μ+μ−Z'过程的截面上限的90%信心级.
- 限制了Z'玻色子的合,范围从3×10−3到1为Z'质量高达8GeV/c2.
结论:
- 贝尔II实验在这个特定的搜索通道中没有发现预测的Z'玻色子的证据.
- 结果对标准模型的LμLτ扩展的参数空间设置了约束.
- 贝尔II的进一步数据收集和分析将提高对这些奇特粒子的敏感性.
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