On high energy exclusive leptoproduction of the rho meson up to twist 3
  The Regge inspired k_T-factorization scheme expresses the scattering amplitude for exclusive leptoproduction of a light vector meson rho in terms of two impact factors, one for the gamma* - rho transition and the other one for the nucleon to nucleon transition, with, at leading order, a two "reggeized" gluon exchange in the t-channel. We report here on a recent phenomenological study where we apply a previously developped scheme which consistently takes into account the twist 3 distribution amplitudes for transversely polarized rho meson. The computation of the gamma* to rho impact factor are performed within collinear factorization of QCD, up to the twist 3 level, based on the Collinear Factorization scheme applied to the amplitudes gamma*g to g rho .   Our results are in good agreement with high energy experimental data for the ratios of helicity amplitudes. 
I. V. Anikin, A. Besse, D.Yu. Ivanov, B. Pire, L. Szymanowski, S.   Wallon
hep-ph hep-ex nucl-ex nucl-th