${\Xi }_c(3055)$ as a scaling point to establish the excited ${\Xi }_c^{(\prime )}$ family

Abstract

The low-lying orbital excitations of ${\Xi }_c^{(\prime )}$ baryons are studied within the chiral quark model combined with the ${}^3{P}_0$ decay mechanism. Motivated by the LHCb observation that ${\Xi }_c(3055)$ is a $\lambda$-mode $1D$ state with $J^P=3/2^{+}$, we take it as a reference to constrain model parameters and perform a systematic analysis of states below 3.1 GeV. Our results provide a consistent interpretation of the observed ${\Xi }_c$ spectrum: ${\Xi }_c(2790)$ and ${\Xi }_c(2815)$ are well described as a $\lambda$-mode $1P$ doublet, the structures around 2.9 GeV can be interpreted as $P$-wave excitations with mixed $\lambda /\rho$ modes, and ${\Xi }_c(2970)$ is consistent with a $2S$ assignment. Furthermore, ${\Xi }_c(3055)$ together with ${\Xi }_c(3080)$ forms a $\lambda$-mode $D$-wave doublet, while ${\Xi }_c(3123)$ favors a $1D$ assignment. These results provide a coherent picture of the low-lying ${\Xi }_c$ spectrum and call for further experimental tests.