Semileptonic B{yields}{pi} decays from an Omnes improved nonrelativistic constituent quark model

Journal Article · Mon Aug 01 00:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.033002· OSTI ID:20711192

Albertus, C; Nieves, J ^[1]; Flynn, J M ^[2]; Hernandez, E; Verde-Velasco, J M ^[3]

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1. Departamento de Fisica Moderna, Universidad de Granada, E-18071 Granada (Spain)
2. School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom)
3. Grupo de Fisica Nuclear, Facultad de Ciencias, E-37008 Salamanca (Spain)

The semileptonic B{yields}{pi}l{sup +}{nu}{sub l} decay is studied starting from a simple quark model which includes the influence of the B* pole. To extend the predictions of a nonrelativistic constituent quark model from its region of applicability near q{sub max}{sup 2}=(m{sub B}-m{sub {pi}}){sup 2} to all q{sup 2} values accessible in the physical decay, we use a novel multiply subtracted Omnes dispersion relation, which considerably diminishes the form-factor dependence on the elastic {pi}B{yields}{pi}B scattering amplitudes at high energies. By comparison to the experimental branching fraction we extract |V{sub ub}|=0.0034{+-}0.0003(exp){+-}0.0007(theory). To further test our framework, we also study D{yields}{pi} and D{yields}K decays and find excellent results f{sub {pi}}{sup +}(0)/f{sub K}{sup +}(0)=0.80{+-}0.03, B(D{sup 0}{yields}{pi}{sup -}e{sup +}{nu}{sub e})/B(D{sup 0}{yields}K{sup -}e{sup +}{nu}{sub e})=0.079{+-}0.008. In particular for the D{yields}{pi} case, we reproduce, with high accuracy, the three-flavor lattice QCD results recently obtained by the Fermilab-MILC-HPQCD Collaboration. While for the D{yields}K case, we successfully describe the data for f{sup +}(q{sup 2})/f{sup +}(0) recently measured by the FOCUS Collaboration.

• OSTI ID: 20711192
• Journal Information: Physical Review. D, Particles Fields, Vol. 72, Issue 3; Other Information: DOI: 10.1103/PhysRevD.72.033002; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
BRANCHING RATIO
COMPARATIVE EVALUATIONS
D MESONS
DISPERSION RELATIONS
ELECTRON NEUTRINOS
ELECTRONS
FERMILAB
FLAVOR MODEL
FORM FACTORS
KAONS MINUS
LATTICE FIELD THEORY
MESON-MESON INTERACTIONS
PIONS MINUS
POSITRONS
QUANTUM CHROMODYNAMICS
SCATTERING AMPLITUDES
SEMILEPTONIC DECAY