Final-state rescattering in B̄⁰₍ₛ₎→ Λ ⁺cΛ ̄⁻c decays

The LHCb Collaboration has recently reported the first observation of the decay B̄ₛ⁰→ Λ c⁺Λ ̄c⁻ B ¯ s 0 → Λ c + Λ ¯ c - , along with measurements of the branching fractions for both B̄⁰→ Λ c⁺Λ ̄c⁻ B ¯ 0 → Λ c + Λ ¯ c - and B̄ₛ⁰→ Λ c⁺Λ ̄c⁻ B ¯ s 0 → Λ c + Λ ¯ c - . In this work, we investigate these two decays within the framework of final state re-scattering. Our results show that the predicted branching fractions are consistent with the experimental measurements, which indicates the significant role of long-distance final-state interactions in such baryonic B decays. Furthermore, we present predictions for the direct CP asymmetries and the asymmetry parameters. Numerically, both decays exhibit nearly vanishing direct CP asymmetries and suppressed longitudinal polarizations α α , whereas the sizable values of β β and γ γ reflect strong interference between the two helicity amplitudes and provide sensitive probes of the decay dynamics.