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Direct CP Violation in Λ_b -> n (Λ)π^+π^- Decays via ρ-ωMixing

X. -H. Guo·A. W. Thomas
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Abstract

We study direct CP violation in the bottom baryon decays Λ_b -> f ρ^0 (ω) -> fπ^+π^- (f=n or Λ). It is found that in these decays via ρ-ωmixing the CP violation could be very large when the invariant mass of the π^+π^- pair is in the vicinity of the ωresonance. With a typical value N_c =2 in the factorization approach, the maximum CP-violating asymmetries are more than 50% and 68% for Λ_b -> n π^+π^- and Λ_b -> Λπ^+π^-, respectively. With the aid of heavy quark symmetry and phenomenological models for the hadronic wave functions of Λ_b, Λand the neutron, we estimate the branching ratios of Λ_b -> n (Λ)ρ^0.

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X. -H. Guo, A. W. Thomas. 1998-05-15. Direct CP Violation in Λ_b -> n (Λ)π^+π^- Decays via ρ-ωMixing. https://doi.org/10.1103/physrevd.58.096013

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