论文标题
$ c \ bar c c \ bar c $状态的简单频谱在动态diquark模型中
The Simple Spectrum of $c\bar c c\bar c$ States in the Dynamical Diquark Model
论文作者
论文摘要
我们开发了$ c \ bar c c \ bar c $的光谱和在动态diquark模型中的其他全面四夸克状态。以最小的模型形式（例如，每个diquark仅出现在色三重组合中；非轨道自旋耦合仅连接每个diquark中的夸克），光谱非常简单。也就是说，$ s $ - 波的多重组完全包含3个堕落的状态（$ 0^{++} $，$ 1^{+ - } $，$ 2^{++} $）和7 $ p $ -Wave状态满足张量的平等间隔规则时满足张量的规则。与最近的LHCB结果进行比较时，我们发现最好的解释是将$ x（6900）$分配给$ 2S $倍数，而较低的状态建议约为$ 6740 $ MEV，非常适合$ 1P $ $ Multiplet的成员。我们还预测了其他多重组的位置（$ 1S $，$ 1D $等），并讨论$ cc $开放风味阈值的意义。
We develop the spectroscopy of $c\bar c c\bar c$ and other all-heavy tetraquark states in the dynamical diquark model. In the most minimal form of the model (e.g., each diquark appears only in the color-triplet combination; the non-orbital spin couplings connect only quarks within each diquark), the spectroscopy is extremely simple. Namely, the $S$-wave multiplets contain precisely 3 degenerate states ($0^{++}$, $1^{+-}$, $2^{++}$) and the 7 $P$-wave states satisfy an equal-spacing rule when the tensor coupling is negligible. When comparing numerically to the recent LHCb results, we find the best interpretation is assigning $X(6900)$ to the $2S$ multiplet, while a lower state suggested at about $6740$ MeV fits well with the members of the $1P$ multiplet. We also predict the location of other multiplets ($1S$, $1D$, etc.) and discuss the significance of the $cc$ open-flavor threshold.
