We calculate the strong decay couplings for $\rho \to \pi\pi$, $\phi\to KK$, $K^* \to K\pi$ and $D^*\to D\pi$ in a unified and consistent approach based on the impulse approximation, nonperturbative solutions of the quark-gap equation and the Poincar\'e invariant Bethe-Salpeter amplitudes of vector and pseudoscalar mesons. In particular, we obtain the coupling $g_{ D^*\!D\pi} = 17.24^{ +3.06}_{ -2.30} $ in very good agreement with the experimental value by CLEO, which corresponds to a strong effective coupling between heavy vector and pseudoscalar mesons to the pion of $\hat g = 0.58^{ +0.10}_{ -0.08}$.
Categories: hep-ph hep-ex hep-lat nucl-th