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Note on the Extraction of |V_{ub}| using Radiative B Decays

Matthias Neubert
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Abstract

The element |V_{ub}| of the quark mixing matrix can be extracted with small theoretical uncertainties by combining weighted integrals over the endpoint regions of the lepton spectrum in B -> X_u l nu decays and the photon spectrum in B -> X_s gamma decays. The perturbative corrections to this determination are computed at next-to-leading order including operator mixing, which has an important impact. The effect of Sudakov resummation is shown to be numerically insignificant.

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Matthias Neubert. 2001-06-08. Note on the Extraction of |V_{ub}| using Radiative B Decays. https://doi.org/10.1016/s0370-2693(01)00668-2

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