最近观察到的$P_c$作为分子状态和可能的混合物$P_c(4457)$
Recently observed $P_c$ as molecular states and possible mixture of $P_c(4457)$
摘要：
最近观察到的$P_c$状态的光谱表现出与$Σ_c \bar{D}^{(*)}$阈值的强关联。尽管分子解释是成功的，但我们仍然想知道是否存在更精细的结构。利用考虑重夸克对称性和手征对称性的有效拉格朗日量以及瞬时Bethe-Salpeter方程，我们研究了$Σ_c \bar{D}^{(*)}$相互作用和三个$P_c$态.我们确认$P_c(4312)$和$P_c(4440)$分别是具有自旋$\frac12$的$Σ_c \bar{D}$和$Σ_c \bar{D}^{*}$分子的良好候选物。与其他分子计算不同，我们的结果表明$P_c(4457)$信号可能是自旋- $\frac32$和自旋- $\frac12$ $Σ_c \bar{D}^{*}$分子的混合物，其中后者似乎是$P_c(4440)$的激发。因此，我们得出结论，面对三个LHCb $P_c$信号，可能存在的不是三个，而是四个分子状态。
英文摘要：
Recently observed spectrum of $P_c$ states exhibits a strong link to $Σ_c \bar{D}^{(*)}$ thresholds. In spite of successful molecular interpretations, we still push forward to wonder whether there exist finer structures. Utilizing the effecitve lagrangians respecting heavy quark symmetry and chiral symmetry, as well as instantaneous Bethe-Salpeter equations, we investigate the $Σ_c \bar{D}^{(*)}$ interactions and three $P_c$ states. We confirm that $P_c(4312)$ and $P_c(4440)$ are good candidates of $Σ_c \bar{D}$ and $Σ_c \bar{D}^{*}$ molecules with spin-$\frac12$, respectively. Unlike other molecular calculations, our results indicate $P_c(4457)$ signal might be a mixture of spin-$\frac32$ and spin-$\frac12$ $Σ_c \bar{D}^{*}$ molecules, where the latter one appears to be an excitation of $P_c(4440)$. Therefore we conclude that, confronting three LHCb $P_c$ signals, there may exist not three, but four molecular states.
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。
