Pion distribution amplitude -- from theory to data

Abstract

We describe the present status of the pion distribution amplitude as originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates, and (ii) a NLO QCD analysis of the CLEO data on F^{\gamma\gamma^*\pi}(Q^2), supplemented by the E791 data on diffractive dijet production, and the JLab F(pi) data on the pion electromagnetic form factor.

Comments: Invited talk given at the Bogolyubov Conference "Problems of Theoretical and Mathematical Physics", Moscow--Dubna, Russia, 2--6 September, 2004, and at the International Conference "Quark Confinement and Hadron Spectrum VI 2004", Villasimius (Cagliary), Sardinia, Italy, 21--25 September, 2004; 5pp., 3 figures