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在sqrt[s]=13.6 TeV的质子对质子碰撞中寻找罕见衰变D^{0}→μ^{+}μ^{-}
V Chekhovsky1, A Hayrapetyan1, V Makarenko1
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|October 25, 2025
概括
研究人员使用13.6 TeV的质子对质子碰撞来寻找罕见的D^{0}→μ^{+}μ^{-}衰变. 该研究设定了对魅力部门风味变化的中性电流衰变的最严格的上限,B(D^{0}→μ^{+}μ^{-}) <2.4×10^{-9}.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 味道物理学的物理
背景情况:
- 魔力介子的罕见衰变提供了标准模型的敏感探测器.
- 风味变化的中性电流 (FCNC) 衰变在标准模型中被高度抑制,使得它们的观察成为新物理学的标志.
研究的目的:
- 为了寻找罕见的衰变D^{0}→μ^{+}μ^{-}.
- 设置这个衰变的分支部分的上限.
- 为了探讨FCNC在魅力领域的相互作用.
主要方法:
- 由CMS探测器收集的sqrt[s]=13.6 TeV的质子对质子碰撞数据.
- 分析了64.5 fb^{-1} 的集成亮度.
- 使用了一个新开发的包容性 dimuon 触发器.
- 从D^{*+}→D^{0}π^{+}衰变中重建了D^{0}质子.
主要成果:
- 没有观察到D^{0}→μ^{+}μ^{-}事件的显著过多.
- 在95%的置信级别下设置了分支分数的上限:B(D^{0}→μ^{+}μ^{-}) <2.4×10^{-9}.
结论:
- 这一结果提供了迄今为止关于魅力行业中任何FCNC衰变的最严格的上限.
- 搜索扩展了CMS风味物理程序的功能,提供了一个新的 dimuon触发器.
- 这些发现限制了潜在的新物理场景,有助于吸引FCNC衰变.
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