On the Form Factors of the $D_{s}^{+}\to \phi\mu^{+}\nu_{\mu} decay

Abstract

We apply the infinite mass effective theory, when a heavy quark mass tends to infinity, and Chiral perturbation theory at the quark level, based on the extended Nambu -- Jona -- Lasinio model with linear realization of chiral $U(3)\times U(3)$ symmetry, to calculate the form factors of the $D_s^{+}\to \varphi {\mu }^{+}{\nu }_{\mu }$ decay up to the first order in current $s$ -- quark mass. The theoretical results are compared with experimental data and found to be in good agreement.

Comments: 7pages, latex, no figures