Title: The baryo-quarkonium picture for hidden-charm and bottom pentaquarks and LHCb $P_{\rm c}(4380)$ and $P_{\rm c}(4450)$ states Show Chinese title

Title: 隐藏魅和底五夸克的重子-夸克环图像及LHCb$P_{\rm c}(4380)$和$P_{\rm c}(4450)$状态

Abstract: We study baryo-charmonium [$\eta_{\rm c}$- and $J/\psi$-$N^*$, $\eta_{\rm c}(2S)$-, $\psi(2S)$- and $\chi_{\rm c}(1P)$-$N$] and baryo-bottomonium [$\eta_{\rm b}(2S)$-, $\Upsilon(2S)$- and $\chi_{\rm b}(1P)$-$N$] bound states, where $N$ is the nucleon and $N^*$ a nucleon resonance. In the baryo-quarkonium model, the five $qqq Q \bar Q$ quarks are arranged in terms of a heavy quarkonium core, $Q \bar Q$, embedded in light baryonic matter, $qqq$, with $q = u$ or $d$. The interaction between the $Q \bar Q$ core and the light baryon can be written in terms of the QCD multipole expansion. The spectrum of baryo-charmonium states is calculated and the results compared with the existing experimental data. In particular, we can interpret the recently discovered $P_{\rm c}(4380)$ and $P_{\rm c}(4450)$ pentaquarks as $\psi(2S)$-$N$ and $\chi_{\rm c2}(1P)$-$N$ bound states, respectively. We observe that in the baryo-bottomonium sector the binding energies are, on average, slightly larger than those of baryo-charmonia. Because of this, the hidden-bottom pentaquarks are more likely to form than their hidden-charm counterparts. We thus suggest the experimentalists to look for five-quark states in the hidden-bottom sector in the $10.4-10.9$ GeV energy region. Show Chinese abstract

Abstract: 我们研究重子-charm介子 [$\eta_{\rm c}$- 和 $J/\psi$-$N^*$, $\eta_{\rm c}(2S)$-, $\psi(2S)$- 和 $\chi_{\rm c}(1P)$-$N$] 和重子-bottom介子 [$\eta_{\rm b}(2S)$-, $\Upsilon(2S)$- 和 $\chi_{\rm b}(1P)$-$N$] 绑定态，其中 $N$是核子，$N^*$是一个核子共振态。 在重子-夸克偶素模型中，五个$qqq Q \bar Q$夸克按一个重夸克偶素核心，$Q \bar Q$，嵌入轻重子物质，$qqq$，带有$q = u$或$d$。 $Q \bar Q$核心与轻重子之间的相互作用可以用QCD多极展开来表示。 计算了重子--charmonium态的谱，并将结果与现有的实验数据进行了比较。 特别是，我们可以将最近发现的$P_{\rm c}(4380)$和$P_{\rm c}(4450)$五夸克解释为$\psi(2S)$-$N$和$\chi_{\rm c2}(1P)$-$N$的束缚态，分别。 我们观察到在重子-底夸克介子区，结合能平均上比重子-魅夸克介子的大一些。 因此，隐底五夸克更可能形成，而不是它们的隐魅对应物。 因此，我们建议实验学家在$10.4-10.9$GeV 能量区域寻找隐底区的五夸克态。