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寻找D^{0}质子在两个质子中的罕见衰变
R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3
1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.
Physical review letters
|August 11, 2023
概括
研究人员使用LHCb数据寻找罕见的D^{0}→μ^{+}μ^{-}衰变. 没有发现任何信号,设置了一个新的世界世界.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 标准模型物理学的标准模型.
背景情况:
- 粒子物理学的标准模型预测了罕见的衰变.
- 衰变D^{0}→μ^{+}μ^{-}是高度抑制的.
- 寻找这种衰变的研究探讨了超越标准模型的新物理学.
研究的目的:
- 为了寻找罕见的衰变D^{0}→μ^{+}μ^{-}.
- 对这种衰变的分支部分设置严格的限制.
- 为了限制新的物理模型.
主要方法:
- 利用了来自LHCb实验的数据,用于7,8和13 TeV的质子对质子碰撞.
- 分析的整合亮度为9 fb^{-1}.
- 从D^{*+}→D^{0}π^{+}衰变中优化搜索D^{0}质子.
主要成果:
- 没有发现过多事件超过预期背景的证据.
- 分支分数的上限设定为B{D^{0}→μ^{+}μ^{-}) <3.1×10^{-9} 在90%C.L.时.
- 这是迄今为止世界上最严格的限制.
结论:
- 搜索对D^{0}→μ^{+}μ^{-}衰变的分支分数施加了强烈的约束.
- 这些结果限制了超越标准模型的物理理论模型.
- 进一步的搜索可能会提高对这种罕见衰变的敏感性.
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