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Theory of Beauty Lifetimes

Matthias Neubert
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Abstract

A critical review of the theoretical understanding of the lifetimes of beauty hadrons is given. A model-independent analysis using the heavy-quark expansion allows for a description of the lifetime ratios tau(B-)/tau(B0) and tau(Lambda_b)/tau(B0) in a small region of parameter space. It is demonstrated that the lifetime ratio tau(B-)/tau(B0) cannot be used to extract the decay constant of the B meson. Implications for the semileptonic branching ratio and charm yield in B decays are pointed out.

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Matthias Neubert. 1997-07-02. Theory of Beauty Lifetimes. https://doi.org/10.1142/9789814503952_0009

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