Abstract
More than two decades ago, we studied heavy-flavor-conserving weak decays of heavy baryons within the framework that incorporates both heavy-quark and chiral symmetries. In view of the first observation of Ξ − b → Λ 0 b π − by LHCb recently, we have reexamined these decays and presented updated predictions. The predicted rates for Ξ − b → Λ 0 b π − in the MIT bag and diquark models are consistent with experiment. The major theoretical uncertainty stems from the evaluation of baryon matrix elements. The branching fraction of Ξ c → Λ c π is predicted to be of order 10−4. It is suppressed relative to \( \mathrm{\mathcal{B}}\left({\Xi}_b\to {\Lambda}_b\pi \right) \) owing to the shorter lifetime of Ξ c relative to Ξ b and the destructive nonspectator W-exchange contribution. The kinematically accessible weak decays of the sextet heavy baryon Ω Q are Ω Q → Ξ Q π. Due to the absence of the \( {\mathrm{\mathcal{B}}}_6-{\mathrm{\mathcal{B}}}_{{}_3^{-}} \) transition in the heavy quark limit and the \( {\mathrm{\mathcal{B}}}_6-{\mathrm{\mathcal{B}}}_6 \) transition in the model calculations, Ω Q → Ξ Q π vanish in the heavy quark limit.
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ArXiv ePrint: 1512.01276
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Cheng, HY., Cheung, CY., Lin, GL. et al. Heavy-flavor-conserving hadronic weak decays of heavy baryons. J. High Energ. Phys. 2016, 28 (2016). https://doi.org/10.1007/JHEP03(2016)028
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DOI: https://doi.org/10.1007/JHEP03(2016)028