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Non-spectator Contributions To The Lifetime of $Λ_{b}$

Chao-Hsi Chang·Peng Guo·Xue-Qian Li·Guo-Li Wang
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Abstract

In this work, we evaluate the contributions of non-spectator effects to the lifetimes of $Λ_b$ and B-mesons. Based on the well-established models and within a reasonable range of the concerned parameters, the contributions can reduce the lifetime of $Λ_b$ by $7 \sim 8%$ compared to that of B-mesons which are not significantly affected. This might partly explain the measured ratio $τ(Λ_{b})/τ(B^{0})=0.79 $ \cite{Data}, which has been a long-standing discrepancy between theory and experimental data.

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Chao-Hsi Chang, Peng Guo, Xue-Qian Li, Guo-Li Wang. 2003-04-15. Non-spectator Contributions To The Lifetime of $Λ_{b}$. https://doi.org/10.1088/0253-6102%2F42%2F5%2F723

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