End-point behavior of the pion distribution amplitude
arXiv:1010.4711
Abstract
We discuss the end-point behavior of the pion distribution amplitude (DA) and calculate its slope using QCD sum rules with nonlocal condensates. This is done in terms of the standard derivative and also with the help of an "integral derivative", recently obtained by us. Our approach favors a value of the slope of the order (or less) of the asymptotic DA and is in clear disagreement with flat-type pion DAs.
13 pages, 5 figures, 3 tables, invited talk given by the second author at "QUARKS-2010, 16th International Seminar on High Energy Physics", Kolomna, Russia, 6-12 June, 2010. v2 An important reference is added with a corresponding insertion in the text. v3 minor typos corrected