Eur. Phys. J. C (2003) 29: 353-364
https://doi.org/10.1140/epjc/s2003-01238-9

Original Paper

Electroproduction of vector mesons: factorization of end-point contributions

Naturwissenschaftlich-Theoretisches Zentrum und Institut für Theoretische Physik, Universität Leipzig, Augustusplatz 10, 04109, Leipzig, Germany

^* e-mail: Alexander.Ivanov@itp.uni-leipzig.de

Abstract

The end-point contributions in the quark longitudinal momentum fraction of the virtual photon ($\gamma^*$) to vector meson (V) impact factor to the diffractive electroproduction amplitude can be factorized in terms of a generalized parton evolution of the target parton distribution. This result is used to model the helicity amplitudes $\gamma^* p \rightarrow V p$ in terms of small x generalized parton distributions.