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


Abstract in English

We report on recent measurements of the branching fractions (BFs) for the decay channels B^0 -> {pi}^-l^+{ u}, B^+ -> {pi}^0l^+{ u}, B^+ -> {eta}l^+{ u}, B^+ -> {eta}l^+{ u}, B^0 -> {rho}^-l^+{ u} and B^+ -> {rho}^0l^+{ u}. We obtain very precise values of the total branching fractions for these decays, as well as partial branching fractions as a function of q^2 for the decay channels B^0 -> {pi}^-l^+{ u}, B^+ -> {eta}l^+{ u} and B^0 -> {rho}^-l^+{ u}. In particular, we use the partial branching fractions of the B^0 -> {pi}^-l^+{ u} 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.

Download