Light vector meson photoproduction at large momentum transfer

We have studied in perturbative QCD all independent helicity amplitudes des cribing the photoproduction of light vector mesons at large t. We found a n ew hard production mechanism which is related to the possibility for a real photon to fluctuate into a massless q (q) over bar pair in a chiral-odd sp in configuration. Each helicity amplitude is given as a sum of chiral-even contribution (when the helicities of quark and antiquark are antiparallel) and this additional chiral-odd part (where the helicities of quark and anti quark are parallel). All amplitudes are expressed in terms of short distanc e asymptotics of the light-cone wave functions of vector meson and photon. The chiral-odd contribution is large, it leads to a dominance of the non sp in-flip amplitude in a very broad region of intermediately high /t/.