HAL : in2p3-00000658, version 1
 arXiv : hep-ph/9805380
 Physical Review Letters 81 (1998) 1782-1785
 Probing partonic structure in $\gamma* \gamma \longrightarrow \pi \pi$ near threshold.
 (1998)
 Hadron pair production gamma* gamma -> h hbar in the region where the c.m. energy is much smaller than the photon virtuality can be described in a factorized form, as the convolution of a partonic handbag diagram and generalized distribution amplitudes which are new non-perturbative functions describing the exclusive fragmentation of a quark-antiquark pair into two hadrons. Scaling behavior and a selection rule on photon helicity are signatures of this mechanism. The case where h is a pion is emphasized.
 Thème(s) : Physique/Physique des Hautes Energies - Phénoménologie
 Lien vers le texte intégral : http://fr.arXiv.org/abs/hep-ph/9805380
 in2p3-00000658, version 1 http://hal.in2p3.fr/in2p3-00000658 oai:hal.in2p3.fr:in2p3-00000658 Contributeur : Peggy Bardon <> Soumis le : Vendredi 5 Mai 2006, 11:56:09 Dernière modification le : Vendredi 5 Mai 2006, 13:32:38