Study of B{yields}{pi}l{nu} and B{yields}{rho}l{nu} decays and determination of |V{sub ub}|

Journal Article · Tue Feb 01 04:00:00 EST 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.032007· OSTI ID:21504850

Amo Sanchez, P del; Lees, J P; Poireau, V; Prencipe, E; Tisserand, V ^[1]; Garra Tico, J; Grauges, E ^[2]; Martinelli, M; Palano, A; Pappagallo, M ^[3]; Eigen, G; Stugu, B; Sun, L ^[4]; Battaglia, M; Brown, D N; Hooberman, B; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L ^[5]

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1. Laboratoire d'Annecy-le-Vieux de Physique des Particules (LAPP), Universite de Savoie, CNRS/IN2P3, F-74941 Annecy-Le-Vieux (France)
2. Facultat de Fisica, Departament ECM, Universitat de Barcelona, E-08028 Barcelona (Spain)
3. INFN Sezione di Bari, I-70126 Bari (Italy)
4. Institute of Physics, University of Bergen, N-5007 Bergen (Norway)
5. Lawrence Berkeley National Laboratory and University of California, Berkeley, California 94720 (United States)

We present an analysis of exclusive charmless semileptonic B-meson decays based on 377x10{sup 6} BB pairs recorded with the BABAR detector at the {Upsilon}(4S) resonance. We select four event samples corresponding to the decay modes B{sup 0}{yields}{pi}{sup -}l{sup +}{nu}, B{sup +}{yields}{pi}{sup 0}l{sup +}{nu}, B{sup 0}{yields}{rho}{sup -}l{sup +}{nu}, and B{sup +}{yields}{rho}{sup 0}l{sup +}{nu} and find the measured branching fractions to be consistent with isospin symmetry. Assuming isospin symmetry, we combine the two B{yields}{pi}l{nu} samples, and similarly the two B{yields}{rho}l{nu} samples, and measure the branching fractions B(B{sup 0}{yields}{pi}{sup -}l{sup +}{nu})=(1.41{+-}0.05{+-}0.07)x10{sup -4} and B(B{sup 0}{yields}{rho}{sup -}l{sup +}{nu})=(1.75{+-}0.15{+-}0.27)x10{sup -4}, where the errors are statistical and systematic. We compare the measured distribution in q{sup 2}, the momentum transfer squared, with predictions for the form factors from QCD calculations and determine the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}|. Based on the measured partial branching fraction for B{yields}{pi}l{nu} in the range q{sup 2}<12 GeV{sup 2} and the most recent QCD light-cone sum-rule calculations, we obtain |V{sub ub}|=(3.78{+-}0.13{sub -0.40}{sup +0.55})x10{sup -3}, where the errors refer to the experimental and theoretical uncertainties. From a simultaneous fit to the data over the full q{sup 2} range and the FNAL/MILC lattice QCD results, we obtain |V{sub ub}|=(2.95{+-}0.31)x10{sup -3} from B{yields}{pi}l{nu}, where the error is the combined experimental and theoretical uncertainty.

• OSTI ID: 21504850
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 3 Vol. 83; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
BEAUTY MESONS
BEAUTY PARTICLES
BOSONS
BRANCHING RATIO
COMPARATIVE EVALUATIONS
DECAY
DIMENSIONLESS NUMBERS
DISTRIBUTION
ELEMENTARY PARTICLES
EQUATIONS
EVALUATION
FIELD THEORIES
FORECASTING
FORM FACTORS
HADRONS
ISOSPIN
KOBAYASHI-MASKAWA MATRIX
LIGHT CONE
MATRICES
MESONS
MOMENTUM TRANSFER
PARTICLE DECAY
PARTICLE PROPERTIES
PIONS
PIONS MINUS
PIONS NEUTRAL
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
RESONANCE
SEMILEPTONIC DECAY
SPACE-TIME
SUM RULES
SYMMETRY
VECTOR MESONS
WEAK PARTICLE DECAY