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Memo on Extracting |V(cb)| and |V(ub)/V(cb)| from semileptonic B decays

I. I. Bigi
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Abstract

Heavy Quark Expansions for semileptonic decays of beauty hadrons are briefly reviewed. I analyze how $|V(cb)|$ can be extracted from the semileptonic width of $B$ mesons, the average semileptonic width of all weakly decaying beauty hadrons and from $B \ra l νD^*$ at zero recoil. Special attention is paid to present theoretical uncertainties (including correlations among them) and on how to reduce them in the future. Finally I will comment on theoretical uncertainties in $|V(ub)/V(cb)|$.

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I. I. Bigi. 1999-07-07. Memo on Extracting |V(cb)| and |V(ub)/V(cb)| from semileptonic B decays. https://arxiv.org/abs/hep-ph/9907270

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