Studies of exclusive charmless semileptonique B decays and extraction of |V_{ub}| at BABAR

Published 12 Jan 2011 in hep-ex | (1101.2439v1)

Abstract: We report on recent measurements of the branching fractions (BFs) for the decay channels B⁰ -> {\pi}^{-\l^+{\nu},} B⁺ -> {\pi}^{0\l^+{\nu},} B⁺ -> {\eta}\l^+{\nu}, B⁺ -> {\eta}'\l^+{\nu}, B⁰ -> {\rho}^{-\l^+{\nu}} and B⁺ -> {\rho}^{0\l^+{\nu}.} We obtain very precise values of the total branching fractions for these decays, as well as partial branching fractions as a function of q² for the decay channels B⁰ -> {\pi}^{-\l^+{\nu},} B⁺ -> {\eta}\l^+{\nu} and B⁰ -> {\rho}^{-\l^+{\nu}.} In particular, we use the partial branching fractions of the B⁰ -> {\pi}^{-\l^+{\nu}} decay channel and form-factor calculations to extract several values of |V_{ub}|. When we compared these values of |V_{ub}| to the one measured in inclusive semileptonic B decay, we find that two of them are consistent, within large theoretical uncertainties.