Light Mesons elm Form Factor and Running Coupling Effects

Abstract

The pion and kaon electromagnetic form factors $F_{M}(Q^2)$ are calculated at the leading order of pQCD using the running coupling constant method. In computations dependence of the meson distribution amplitudes on the hard scale $Q^2$ is taken into account. The Borel transform and resummed expression for $F_{M}(Q^2)$ are found. The effect of the next-to-leading order term in expansion of $\alpha_{S}(\lambda Q^2)$ in terms of $\alpha_{S}(Q^2)$ on the pion form factor $F_{\pi}(Q^2)$ is discussed, comparison is made with the infrared matching scheme's result.