High energy rho meson leptoproduction
We investigate the longitudinal and transverse polarized cross-sections of the leptoproduction of the rho meson in the high energy limit. Our model is based on the computation of the impact factor gamma*(lambda_gamma) -> rho(lambda_rho) using the twist expansion in the forward limit and expressed in the impact parameter space. This treatment involves in the final stage the twist 2 and twist 3 distribution amplitudes (DAs) of the rho meson and the dipole scattering amplitude. Taking models that exist for the DAs and for the dipole cross-section, we get a phenomenological model for the helicity amplitudes, we compare our predictions with HERA data and get a fairly good description for large enough virtualities of the photon.