Meson Electro-Magnetic Form Factors in an Extended Nambu--Jona-Lasinio model including Heavy Quark Flavors

Abstract

Based on an extended NJL model including heavy quark flavors, we calculate the form factors of pseudo-scalar and vector mesons. After take into account of the vector-meson-dominance effect which introduce a form factor correction to the quark vector coupling vertices, the form factors and electric radii of ${\pi }^{+}$ and $K^{+}$ of pseudo-scalar meson in light flavor sector fit the experimental data well. Also the magnetic moments of light vector meson ${\rho }^{+}$ and $K^{\ast +}$ are comparable with other theoretical calculation. The form factors in light-heavy flavor sector are presented to confront with future experiments or theoretical calculations.