2004/08/30 by K. Abe, Abe, K.
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.hep-ex/0408145
openalex publication_date 2004/08/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report on a measurement of the charmless semileptonic B decays, B0->pi-l+nu and B0->rho-l+nu, based on 140 fb-1 data collected with the Belle detector at the KEKB e+e- asymmetric collider. In this analysis, accompanying B mesons are reconstructed from semileptonic B->D^(*)lnu decays, which enables us to detect the signal with high purity and with marginal statistics. We found branching fractions of Br(B0->pi-l+nu)=(1.76 ± 0.28 ± 0.20 ± 0.03)10-4 and Br(B0->rho-l+nu)=(2.54 ± 0.78 ± 0.85 ± 0.30)10-4, where the errors are statistical, experimental systematic, systematic due to form-factor uncertainties. We present also the branching fractions in three q2 intervals; q2 < 8, 8 ≤ q2 < 16, q2 ≥ 16 GeV2/c2, for each decay mode. Based on these results, the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vub is extracted. All of the presented results are preliminary.