Extracting the Distribution Amplitudes of the ρ meson from the Color Glass Condensate

Abstract

We extract the twist-2 and twist-3 Distribution Amplitudes (DAs) of the ρ meson using the HERA data on diffractive ρ photoproduction. We do so using several Colour Glass Condensate (CGC) inspired and a Regge inspired dipole models. We find that our extracted twist-2 DA is not much model dependent and is consistent with QCD Sum Rules and lattice predictions. The extracted twist-3 DA is more model dependent but is still consistent with the Sum Rules prediction.