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Measurement of the B{yields}{pi}l{nu} Branching Fraction and Determination of vertical bar V{sub ub} vertical bar with Tagged B Mesons

Journal Article · · Physical Review Letters
; ; ; ; ; ; ; ; ;  [1];  [2];  [3]; ; ; ; ;  [4]; ; ;  [5]
  1. Laboratoire de Physique des Particules, F-74941 Annecy-le-Vieux (France)
  2. Universitat de Barcelona, Facultat de Fisica Dept. ECM, E-08028 Barcelona (Spain)
  3. Universita di Bari, Dipartimento di Fisica and INFN, I-70126 Bari (Italy)
  4. Institute of High Energy Physics, Beijing 100039 (China)
  5. University of Bergen, Institute of Physics, N-5007 Bergen (Norway)
We report a measurement of the B{yields}{pi}l{nu} branching fraction based on 211 fb{sup -1} of data collected with the BABAR detector. We use samples of B{sup 0} and B{sup +} mesons tagged by a second B meson reconstructed in a semileptonic or hadronic decay and combine the results assuming isospin symmetry to obtain B(B{sup 0}{yields}{pi}{sup -}l{sup +}{nu})=(1.33{+-}0.17{sub stat}{+-}0.11{sub syst})x10{sup -4}. We determine the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| by combining the partial branching fractions measured in ranges of the momentum transfer squared and theoretical calculations of the form factor. Using a recent lattice QCD calculation, we find vertical bar V{sub ub} vertical bar =(4.5{+-}0.5{sub stat}{+-}0.3{sub syst}(+0.7/-0.5){sub FF})x10{sup -3}, where the last error is due to the normalization of the form factor.
OSTI ID:
20861396
Journal Information:
Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 21 Vol. 97; ISSN 0031-9007; ISSN PRLTAO
Country of Publication:
United States
Language:
English