Heavytolight form factors: Sum rules on the light cone and beyond
Abstract
We report the first systematic analysis of the offlightcone effects in sum rules for heavytolight form factors. These effects are investigated in a model based on scalar constituents, which allows a technically rather simple analysis but has the essential features of the analogous QCD calculation. The correlator relevant for the extraction of the heavytolight form factor is calculated in two different ways: first, by adopting the full BetheSalpeter amplitude of the light meson and, second, by performing the expansion of this amplitude near the light cone x{sup 2}=0. We demonstrate that the contributions to the correlator from the lightcone term x{sup 2}=0 and the offlightcone terms x{sup 2}{ne}0 have the same order in the 1/m{sub Q} expansion. The lightcone correlator, corresponding to x{sup 2}=0, is shown to systematically overestimate the full correlator, the difference being {approx}{lambda}{sub QCD}/{delta}, with {delta} the continuum subtraction parameter of order 1 GeV. Numerically, this difference is found to be 10 divide 20%.
 Authors:
 Institute for High Energy Physics, Austrian Academy of Sciences, Nikolsdorfergasse 18, A1050, Vienna (Austria)
 (Russian Federation)
 INFN, Sezione di Roma III, Via della Vasca Navale 84, I00146, Rome (Italy)
 Publication Date:
 OSTI Identifier:
 21020515
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.75.096002; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; BETHESALPETER EQUATION; FORM FACTORS; GEV RANGE; LIGHT CONE; MESONS; QUANTUM CHROMODYNAMICS; SUM RULES
Citation Formats
Lucha, Wolfgang, Melikhov, Dmitri, Nuclear Physics Institute, Moscow State University, 119992, Moscow, and Simula, Silvano. Heavytolight form factors: Sum rules on the light cone and beyond. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.096002.
Lucha, Wolfgang, Melikhov, Dmitri, Nuclear Physics Institute, Moscow State University, 119992, Moscow, & Simula, Silvano. Heavytolight form factors: Sum rules on the light cone and beyond. United States. doi:10.1103/PHYSREVD.75.096002.
Lucha, Wolfgang, Melikhov, Dmitri, Nuclear Physics Institute, Moscow State University, 119992, Moscow, and Simula, Silvano. Tue .
"Heavytolight form factors: Sum rules on the light cone and beyond". United States.
doi:10.1103/PHYSREVD.75.096002.
@article{osti_21020515,
title = {Heavytolight form factors: Sum rules on the light cone and beyond},
author = {Lucha, Wolfgang and Melikhov, Dmitri and Nuclear Physics Institute, Moscow State University, 119992, Moscow and Simula, Silvano},
abstractNote = {We report the first systematic analysis of the offlightcone effects in sum rules for heavytolight form factors. These effects are investigated in a model based on scalar constituents, which allows a technically rather simple analysis but has the essential features of the analogous QCD calculation. The correlator relevant for the extraction of the heavytolight form factor is calculated in two different ways: first, by adopting the full BetheSalpeter amplitude of the light meson and, second, by performing the expansion of this amplitude near the light cone x{sup 2}=0. We demonstrate that the contributions to the correlator from the lightcone term x{sup 2}=0 and the offlightcone terms x{sup 2}{ne}0 have the same order in the 1/m{sub Q} expansion. The lightcone correlator, corresponding to x{sup 2}=0, is shown to systematically overestimate the full correlator, the difference being {approx}{lambda}{sub QCD}/{delta}, with {delta} the continuum subtraction parameter of order 1 GeV. Numerically, this difference is found to be 10 divide 20%.},
doi = {10.1103/PHYSREVD.75.096002},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

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