arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1607.02799hep-phhep-exhep-latnucl-ex
收藏

双夸克-反双夸克模型中的隐魅八重态四夸克态

Hidden charm octet tetraquarks from a diquark-antidiquark model

Ruilin Zhu

摘要:

LHCb合作组最近利用$\sqrt s= 7$和$8$ TeV的$p\bar p$碰撞的3个${\rm fb}^{-1}$数据,在衰变过程$B^+\to J/ψϕK^+$中观测到了四种奇异的类粲偶素态,即$X(4140)$、$X(4274)$、$X(4500)$和$X(4700)$.本文系统地研究了隐魅四夸克态的性质。根据味$SU(3)$对称性,隐魅四夸克态形成八重态和单重态。基于双夸克-反双夸克模型,给出了隐魅四夸克谱。先前的XYZ奇异态与新的$X(4140)$、$X(4274)$、$X(4500)$和$X(4700)$一起可以很好地分类为某些表示。计算了XYZ的自旋宇称和质量,大部分与实验数据相符。我们特别发现,$Z_c(4430)$可以看作是$Z_c(3900)$的第一径向激发,而$Y(1^{--})$态可以由$X/Z$态的第一轨道激发得到.此外,我们还计算了隐魅四夸克到两个粲介子的衰变宽度。这一工作给出了XYZ态的一般四夸克态描述,有助于揭示其内部结构。

英文摘要:

Four exotic charmonium-like states, i.e. $X(4140)$, $X(4274)$, $X(4500)$, and $X(4700)$, have been observed very recently by LHCb Collaboration in the decay process $B^+\to J/ψϕK^+$ using the 3${\rm fb}^{-1}$ data of $p\bar p$ collision at $\sqrt s= 7$ and $8$ TeV. In this paper, we investigate systematically the properties of hidden charm tetraquark states. The hidden charm tetraquarks form an octet configuration and a singlet configuration according to flavor $SU(3)$ symmetry. Based on a diquark-antidiquark model, the hidden charm tetraquarks spectra are given. The previous XYZ exotic states altogether with the newly ones $X(4140)$, $X(4274)$, $X(4500)$, and $X(4700)$, can be well classified into certain representations. The spin-parities and masses of the XYZ are predicted, most of which are in agreement with the data. We particularly find that $Z_c(4430)$ may be treated as the first radial excitation of $Z_c(3900)$, while the $Y(1^{--})$ states can be obtained by the first orbital excitation of the $X/Z$ states. Besides, we calculate the decay widths of the hidden charm tetraquarks into two charmed mesons. This work gives a general tetraquark description for the XYZ states, which is helpful to uncover their inner structures.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑