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Updated: Jul 19, 2025

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首次观察到双电荷四子及其中性伴侣

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

研究人员发现了两个新的四夸克状态,一个是双电荷的,一个是中性,分解成D_s和pion对. 这些异国情调的粒子,自旋平价为0+,暗示出一种异旋三重体.

科学领域:

粒子物理学粒子物理学
量子色态动力学 (QCD) 是一个
子光谱学子光谱学

背景情况:

同回旋对称性将粒子的不同电荷状态联系起来,为基本相互作用提供了洞察力.
寻找奇特的子,如四夸克,扩大了我们对QCD的理解,超越了夸克模型.

研究的目的:

为了进行B0和B+分解成D-D_s-pi最终状态的综合振幅分析.
在这些衰变通道中寻找和描述新的共振状态.
研究观察到的异国情态的性质和量子性质.

主要方法:

利用由LHCb探测器记录的7,8和13 TeV的质子-质子碰撞的大数据集.
进行了B^{0}→D[over ̄]^{0}D_{s}^{+}π^{-}和B^{+}→D^{-}D_{s}^{+}π^{+}衰变的综合振幅分析.
使用复杂的数据分析技术确定了共振状态的质量,宽度和旋转平价.

主要成果:

观测到两个新的共振状态,质量约为2.908 GeV,宽度约为0.136 GeV.
确定了第一个双电荷的开放魅力四夸克状态[cs[over ̄]ud[over ̄]]和一个中性四夸克[cs[over ̄]u[over ̄]d].
这两种状态均表现出旋转平价0+,它们的一致参数表明它们形成了同旋转三重组.

结论:

发现这两个四夸克为异国情调的子状态提供了有力的证据.
这些四夸克所观察到的同脊柱三重体性质为研究夸克相互作用提供了一个独特的实验室.
这些发现对QCD.CD预测的复杂子光谱的持续探索做出了重大贡献.

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