Determination of the strong coupling g{sub B*B{pi}} from semileptonic B{yields}{pi}l{nu} decay

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

DOI:https://doi.org/10.1103/PHYSREVD.83.054019· OSTI ID:21578195

Xinqiang, Li ^[1]; Fang, Su ^[2]; Yadong, Yang ^[2]

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1. Department of Physics, Henan Normal University, Xinxiang, Henan 453007 (China)
2. Institute of Particle Physics, Huazhong Normal University, Wuhan, Hubei 430079 (China)

According to heavy-meson chiral perturbation theory, the vector form factor f{sub +}(q{sup 2}) of exclusive semileptonic decay B{yields}{pi}l{nu} is closely related, at least in the soft-pion region (i.e., q{sup 2{approx}}(m{sub B}-m{sub {pi}}){sup 2}), to the strong coupling g{sub B*B{pi}} or the normalized coupling g-circumflex. Combining the precisely measured q{sup 2} spectrum of B{yields}{pi}l{nu} decay by the BABAR and Belle collaborations with several parametrizations of the form factor f{sub +}(q{sup 2}), we can extract these couplings from the residue of the form factor at the B{sup *} pole, which relies on an extrapolation of the form factor from the semileptonic region to the unphysical point q{sup 2}=m{sub B}{sup *2}. Comparing the extracted values with the other experimental and theoretical estimates, we can test these various form-factor parametrizations, which differ from each other by the amount of physical information embedded in. It is found that the extracted values based on the Becirevic-Kaidalov, Ball-Zwicky and Bourrely-Caprini-Lellouch parametrizations are consistent with each other and roughly in agreement with the other theoretical and lattice estimates, while the Boyd-Grinstein-Lebed ansatz, featured by a spurious, unwanted pole at the threshold of the cut, gives a neatly larger value.

• OSTI ID: 21578195
• Journal Information: Physical Review. D, Particles Fields, Vol. 83, Issue 5; Other Information: DOI: 10.1103/PhysRevD.83.054019; (c) 2011 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHIRALITY
COUPLING
EXTRAPOLATION
FORM FACTORS
PERTURBATION THEORY
PIONS
SEMILEPTONIC DECAY
SPECTRA
STRONG-COUPLING MODEL
BOSONS
DECAY
DIMENSIONLESS NUMBERS
ELEMENTARY PARTICLES
HADRONS
MATHEMATICAL MODELS
MATHEMATICAL SOLUTIONS
MESONS
NUMERICAL SOLUTION
PARTICLE DECAY
PARTICLE MODELS
PARTICLE PROPERTIES
PSEUDOSCALAR MESONS
WEAK PARTICLE DECAY