Vector-meson-baryon coupling constants in QCD sum rules

The external-field quantum chromodynamics (QCD) sum rules method is used to evaluate the coupling constants of the vector mesons rho and omega to the nucleon and the Lambda,Sigma, and Xi baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with SU(3)-flavor relations. By assuming ideal mixing, this leads to a determination of the F/(F+D) ratio of the vector-meson octet: we find alphav=1 and alpham=0.18 for the vector and the magnetic F/(F+D) ratios, respectively. The sensitivity of the results to the unknown vacuum susceptibility zeta is discussed. The coupling constants with SU(3)-breaking effects taken into account are also calculated