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Theoretical Uncertainties in Gamma_sl(b->u)

Nikolai Uraltsev
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Abstract

I review the existing theoretical uncertainties in relating the semileptonic decay width in b->u transitions to the underlying Kobayashi-Maskawa mixing element |V_ub|. The theoretical error bars are only a few percent in |V_ub|, with uncertainties from the impact of the nonperturbative effects nearly negligible.

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Nikolai Uraltsev. 1999-06-20. Theoretical Uncertainties in Gamma_sl(b->u). https://doi.org/10.1142/s0217751x99002177

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