On the pion distribution amplitude. Derivation, properties, predictions

Abstract

We provide an in-depth analysis of the $\pi$ distribution amplitude in terms of two different Gegenbauer representations. Detailed predictions for the $\pi -\gamma$ transition form factor are presented, obtained with light-cone sum rules. Various $\pi$ distribution amplitudes are tested and the crucial role of their endpoint behavior in the form-factor analysis is discussed. Comparison with the data is given.

Comments: 7 pages, 3 figures. Based on talk by first author at LIGHTCONE 2014, May 26-30, 2014, Raleigh, NC, USA. Accepted for publication in Few-Body Systems