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arXiv · 0705.3553

|Vub| from exclusive semileptonic B to pi decays revisited

Jonathan M Flynn·Juan Nieves
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Abstract

We update the extraction of |Vub| from exclusive semileptonic B to pi decays, combining experimental partial branching fraction information with theoretical form factor calculations, using the recently revised HPQCD results for the form factors f_+ and f_0. We use Omnes representations to provide the required parametrisations of the form factors. The extracted value is 10^3 |Vub| = 3.47+/-0.29+/-0.03, in striking agreement with |Vub| extracted using all other inputs in CKM fits and showing some disagreement with |Vub| extracted from inclusive semileptonic B to pi decays.

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Jonathan M Flynn, Juan Nieves. 2007-09-04. |Vub| from exclusive semileptonic B to pi decays revisited. https://doi.org/10.1103/physrevd.76.031302

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