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Interpretation of the newly observed $Λ_b(6146)^{0}$ and $Λ_b(6152)^0$ states in a chiral quark model

The strong decays of the low-lying $λ$-mode $Λ_b(1D,2S)$ and $Σ_b(2S)$ states are studied in a chiral quark model. We find that: (i) the newly observed $Λ_b(6146/6152)$ resonances in the $Λ_bπ^+π^-$ spectrum by the LHCb Collaboration might be explained with the $λ$-mode $Λ_b(1D)$ states in the quark model. It should be emphasized that whether the structure in the $Λ_bπ^+π^-$ spectrum correspond to two states or one state should be further clarified with more observations in future experiments. (ii) The $Λ_b(2S)$ $|J^P = \frac{1}{2}^+,0\rangle$ state mainly decays into $Σ_b^*π$ channel, which may be an ideal channel for searching for this $Λ_b(2S)$ state in future experiments. (iii) The $Σ_b(2S)$ $|J^P = \frac{1}{2}^+,1 \rangle$ and $|J^P = \frac{3}{2}^+,1 \rangle$ dominantly decay into $Λ_bπ$ with $Γ\simeq 3.82$ MeV and $Γ\simeq 4.72$ MeV, respectively.