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Enhancement of preasymptotic effects in inclusive beauty decays

B. Guberina·B. Melic·H. Stefancic
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Abstract

We extend Voloshin's recent analysis of charmed and beauty hyperon decays based on SU(3) symmetry and heavy quark effective theory, by introducing a rather moderate model-dependence, in order to obtain more predictive power, e.g. the values of lifetimes of the (Λ_{b},Ξ_{b}) hyperon triplet and the lifetime of Ω_{b}. In this way we obtain an improvement of the ratio τ(Λ_{b})/τ(B_{d}^{0}) \sim 0.9 and the hierarchy of lifetimes τ(Λ_{b}) \simeq τ(Ξ_{b}^{0}) < τ(Ξ_{b}^{-}) < τ(Ω_{b}) with lifetimes of Ξ_{b}^{-} and Ω_{b} exceeding the lifetime of Λ_{b} by 22% and 35%, respectively.

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B. Guberina, B. Melic, H. Stefancic. 1999-07-23. Enhancement of preasymptotic effects in inclusive beauty decays. https://doi.org/10.1016/s0370-2693(99)01198-3

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