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Preasymptotic effects in beauty decays

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

Large preasymptotic effects in beauty decays have been found using heavy-quark and SU(3) symmetry, as well as experimental data on charmed hyperons. Contrary to rather uniform beauty-meson lifetimes, a much larger spread of beauty-baryon lifetimes is predicted. However, it is highly unlikely that, theoretically, the $ τ(Λ_b)/τ(B_d^0) $ ratio, which at present deviates more than $1σ$ from the experimental result, can be lowered below 0.9.

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B. Guberina, B. Melic, H. Stefancic. 2000-02-01. Preasymptotic effects in beauty decays. https://doi.org/10.1142/9789812791870_0024

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