QCD sum rules with nonlocal condensates and the spacelike pion form factor

Journal Article · Fri May 01 04:00:00 EDT 2009 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.79.093010· OSTI ID:21308404

Bakulev, A P; Pimikov, A V; Stefanis, N G ^[1]

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1. Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow region (Russian Federation)

We present a detailed investigation of the spacelike pion's electromagnetic form factor using three-point QCD sum rules that exclusively involve nonlocal condensates. Our main methodological tools are a spectral density which includes O({alpha}{sub s}) corrections, a suitably improved Gaussian ansatz to model the distribution of the average momentum of quarks in the QCD vacuum, and a perturbative scheme that avoids Landau singularities. Using this framework, we obtain predictions for the pion form factor together with error estimates originating from intrinsic theoretical uncertainties owing to the perturbative expansion and the nonperturbative method applied. We also discuss our results in comparison with other calculations, in particular, with those following from the AdS/QCD correspondence. We find good agreement of our predictions with measurements in the range of momenta covered by the existing experimental data between 1 and 10 GeV{sup 2}.

• OSTI ID: 21308404
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 9 Vol. 79; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTI DE SITTER SPACE
COMPARATIVE EVALUATIONS
CONDENSATES
CORRECTIONS
DISTRIBUTION
ELECTROMAGNETIC FORM FACTORS
FORECASTING
PIONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKS
SIMULATION
SINGULARITY
SPECTRAL DENSITY
STRING MODELS
SUM RULES