The gluonic contributions to the conventional PCAC formulas due to flavor singlet axial anomaly have been instrumental in explaining the mass of the $\eta^{ \prime}$ and providing a plausible explanation for solving the spin crisis. We show that they also play an important role in the description of photo- and electroproduction of vector mesons at low energy and high momentum transfers. We calculate the contributions of this type to $\phi$ meson electromagnetic production in a model, which contains also a soft pomeron, and find agreement with recent CLAS data.
Categories: hep-ph hep-ex nucl-th