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arXiv · hep-ph/9711248

Comment on $V_{ub}$ from Exclusive Semileptonic B and D Decays

Zoltan Ligeti·Iain W. Stewart·Mark B. Wise
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Abstract

The prospects for determining $|V_{ub}|$ from exclusive B semileptonic decay are discussed. The double ratio of form factors $(f^{B\toρ}/f^{B\to K^*})/ (f^{D\toρ}/f^{D\to K^*})$ is calculated using chiral perturbation theory. Its deviation from unity due to contributions that are non-analytic in the symmetry breaking parameters is very small. Combining experimental data obtainable from (B->rho l nu), (B->K* l l) and (D->rho l nu) can lead to a model independent determination of $|V_{ub}|$ with an uncertainty from theory of about 10%.

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Zoltan Ligeti, Iain W. Stewart, Mark B. Wise. 1998-03-10. Comment on $V_{ub}$ from Exclusive Semileptonic B and D Decays. https://doi.org/10.1016/s0370-2693(97)01518-9

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