Understanding the newly observed $Ξ_c^0$ states through their decays

Inspired by the newly observed $Ξ_c^0$ states by the LHCb Collaboration, we investigate the OZI-allowed two-body strong decays of the $λ$-mode $1P$ wave $Ξ'_c$ states within the chiral quark model. Our results indicate that: (i) the newly observed states $Ξ_c(2923)^0$ and $Ξ_c(2939)^0$ are good candidates of the $λ$-mode $1P$ wave $Ξ'_c$ states with the spin-parity $J^P=3/2^-$, namely $|^4P_λ3/2^-\rangle$ and $|^2P_λ3/2^-\rangle$, respectively. (ii) The another newly observed state $Ξ_c(2965)^0$ mostly corresponds to the $λ$-mode $1P$-wave $Ξ'_c$ state with the spin-parity $J^P=5/2^-$, namely $|^4P_λ5/2^-\rangle$. (iii) For the two $λ$-mode $J^P=1/2^-$ mixed states, the $|P_λ~1/2^-\rangle_1$ is a narrow state with a width of $Γ\sim15$ MeV and mainly decays into $Ξ'_cπ$; while the $|P_λ~1/2^-\rangle_2$ state has a width of $Γ\sim52$ MeV and dominantly decays into $Ξ_cπ$ and $Λ_cK$ channels. If the broad structure around $2880$ MeV observed at LHCb arises from the new $Ξ^0_c$ state, this state is very likely to be the $|P_λ~1/2^-\rangle_2$ state.

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