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FIZIKA B 17 (2008) 2, 217 - 230
 
PION STRUCTURE IN QCD: FROM THEORY TO LATTICE TO EXPERIMENTAL DATA
A. P. BAKULEVa, S. V. MIKHAILOVa, A. V. PIMIKOVa
and N. G. STEFANISb
aBogoliubov Lab. of Theoretical Physics, JINR, 141980 Dubna,
Russia
E-mail addresses: [email protected],
[email protected],
[email protected]
bITP-II, Ruhr-Universität Bochum, D-44780 Bochum, Germany
E-mail address:
[email protected]
Received 13 October 2007; Accepted 20 February 2008
Online 20 June 2008
We describe the present status of the pion distribution amplitude (DA) as it
originates from several sources: (i) a nonperturbative approach based on QCD sum
rules with nonlocal condensates, (ii) an O(as) QCD analysis of the CLEO data on Fgg*p(Q2) with asymptotic and renormalon models for higher twists
and (iii) recent high-precision lattice QCD calculations of the second moment of
the pion DA. We show predictions for the pion electromagnetic form factor,
obtained in analytic QCD perturbation theory, and compare it with the JLab data
on Fp(Q2). We also discuss in this context an improved model for
nonlocal condensates in QCD and show its consequences for the pion DA and the
gg*®p transition form factor. We include a brief analysis of meson-induced massive
lepton (muon) Drell-Yan production for the process p-N®m+m-X, considering both an unpolarized nucleon target and longitudinally
polarized protons.
PACS numbers: 11.10.Hi, 12.38.Bx, 12.38.Lg, 13.40.Gp
UDC 539.125
Keywords: pion distribution amplitude, electromagnetic form factors, QCD sum
rules, factorization, renormalization group evolution, lattice QCD, Drell-Yan
production
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