Tagging the pion quark structure in QCD
Abstract
We combine the constraints on the pion quark structure available from perturbative QCD, nonperturbative QCD (nonlocal QCD sum rules and lightcone sum rules) with the analysis of current data on F{sub {pi}}{sub {gamma}}{sub {gamma}}{sub *}(Q{sup 2}), including recent highprecision lattice calculations of the second moment of the pion's distribution amplitude. We supplement these constraints with those extracted from the renormalon approach by means of the twistfour contributions to the pion distribution amplitude in order to further increase stability with respect to related theoretical uncertainties. We show which regions in the space of the first two nontrivial Gegenbauer coefficients a{sub 2} and a{sub 4} of all these constraints overlap, tagging this way the pion structure to the highest degree possible at present.
 Authors:
 Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna (Russian Federation)
 Publication Date:
 OSTI Identifier:
 20776906
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.73.056002; (c) 2006 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; ACCURACY; AMPLITUDES; DISTRIBUTION; LATTICE FIELD THEORY; LIGHT CONE; PARTICLE STRUCTURE; PIONS; QUANTUM CHROMODYNAMICS; QUARKS; SUM RULES
Citation Formats
Bakulev, A.P., Mikhailov, S.V., and Stefanis, N.G. Tagging the pion quark structure in QCD. United States: N. p., 2006.
Web. doi:10.1103/PhysRevD.73.056002.
Bakulev, A.P., Mikhailov, S.V., & Stefanis, N.G. Tagging the pion quark structure in QCD. United States. doi:10.1103/PhysRevD.73.056002.
Bakulev, A.P., Mikhailov, S.V., and Stefanis, N.G. Wed .
"Tagging the pion quark structure in QCD". United States.
doi:10.1103/PhysRevD.73.056002.
@article{osti_20776906,
title = {Tagging the pion quark structure in QCD},
author = {Bakulev, A.P. and Mikhailov, S.V. and Stefanis, N.G.},
abstractNote = {We combine the constraints on the pion quark structure available from perturbative QCD, nonperturbative QCD (nonlocal QCD sum rules and lightcone sum rules) with the analysis of current data on F{sub {pi}}{sub {gamma}}{sub {gamma}}{sub *}(Q{sup 2}), including recent highprecision lattice calculations of the second moment of the pion's distribution amplitude. We supplement these constraints with those extracted from the renormalon approach by means of the twistfour contributions to the pion distribution amplitude in order to further increase stability with respect to related theoretical uncertainties. We show which regions in the space of the first two nontrivial Gegenbauer coefficients a{sub 2} and a{sub 4} of all these constraints overlap, tagging this way the pion structure to the highest degree possible at present.},
doi = {10.1103/PhysRevD.73.056002},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 73,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}

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