$\Xi_c(3055)$ 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 $^3P_0$ 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.