Measurement of the branching fractions of B̄→D**ℓ-ν̄ℓ decays in events tagged by a fully reconstructed B meson

Abstract

We report a measurement of the branching fractions of B̄→D* *ℓ-ν̄ℓ decays based on 417fb-1 of data collected at the Υ(4S) resonance with the BABAR detector at the PEP-II e+e- storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D(*)π)- m(D(*)) is performed to extract the signal yields of the different D** states. We observe the B̄→D**ℓ- ν̄ℓ decay modes corresponding to the four D** states predicted by heavy quark symmetry with a significance greater than 5 standard deviations including systematic uncertainties. © 2008 The American Physical Society.