Measurement of the B+→ωl+ν and B+→ηl+ν branching fractions

Abstract

We present a study of the charmless semileptonic B -meson decays B + → ω ℓ + ν and B + → η ℓ + ν . The analysis is based on 3.83 × 10 8 B ¯¯¯ B pairs recorded at the Υ ( 4 S ) resonance with the BABAR detector. The ω mesons are reconstructed in the channel ω → π + π − π 0 and the η mesons in the channels η → π + π − π 0 and η → γ γ . We measure the branching fractions B ( B + → ω ℓ + ν ) = ( 1.14 ± 0.16 stat ± 0.08 syst ) × 10 − 4 and B ( B + → η ℓ + ν ) = ( 0.31 ± 0.06 stat ± 0.08 syst ) × 10 − 4 .