Hard exclusive electroproduction of pseudoscalar mesons and the QCD axial anomaly - art. no. 114025.

Hard exclusive electroproduction of pi 0, eta, eta' masons by longitudinal photons is considered. With the help of the QCD factorization theorem we sh ow that at sufficiently large virtualities Q(2) amplitudes of hard exclusiv e processes may be calculated in terms of the target parton distributions a nd the minimal Fock component of the pseudoscalar meson light cone wave fun ction at zero interquark distances. This result justifies our calculation o f the ratios of the pi(0):eta:eta' yields forlheelectroproduction processes off nucleons and deuterons based on the low energy QCD chiral dynamics, an d the QCD anomaly. [S0556-2821(99)05511-3].