Transition Distribution Amplitudes for gamma* gamma collisions

Abstract

We study the exclusive production of pi-pi and rho-pi in hard gamma* gamma scattering in the forward kinematical region where the virtuality of one photon provides us with a hard scale in the process. The newly introduced concept of Transition Distribution Amplitudes (TDA) is used to perform a QCD calculation of these reactions thanks to two simple models for TDAs. The sizable cross sections for rho-pi and pi-pi production may be tested at intense electron-positron colliders such as CLEO and B factories (Belle and BaBar).

Comments: Talk given at International Conference on the Structure and Interactions of the Photon (Photon 2007), 9-13 Jul 2007, Paris, France; 4 pages, 5 figures, uses photon2007.cls (included)