Meson form factors and nonperturbative gluon propagators

Abstract

The meson (pion and kaon) form factor is calculated in the perturbative framework with alternative forms for the running coupling constant and the gluon propagator in the infrared kinematic region. These modified forms are employed to test the sensibility of the meson form factor to the nonperturbative contributions. It is a powerful discriminating quantity and the results obtained with a particular choice of modified running coupling constant and gluon propagator have good agreement with the available data for both mesons, indicating the robustness of the method of calculation. Nevertheless, the nonperturbative aspects may be included in the perturbative framework of the calculation of exclusive processes.