2005/06/26 by B. Aubert, BABAR Collaboration, Aubert, B. +1
Materials Science · Physics and Astronomy · #Enzyme Structure and Function #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #hep-ex
paper · pdf · doi:10.48550/arxiv.hep-ex/0506064
20 pages, 4 figures, contributed to Lepton-Photon 2005; updated reference
openalex publication_date 2005/06/26 · arxiv created 2005/07/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report preliminary results from a study of the charmless exclusive semileptonic decay B0 -> pi- l+ nu based on the data collected at the Upsilon(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay B0bar -> D(*)+ l- nubar. We extract the total branching fraction BF(B0 -> pi- l+ nu) = (1.03 +/- 0.25(stat.) +/- 0.13(syst.)) x 10-4 and the partial branching fractions in three bins of q2, the invariant mass squared of the lepton-neutrino system. From the partial branching fractions and theoretical predictions for the form factors, we determine the magnitude of the CKM matrix element |Vub|. We find |Vub| = (3.3 +/- 0.4(stat.) +/- 0.2(syst.) +0.8/-0.4(FF)) x 10-3, where the last error is due to normalization of the form factor.