Suppression ofπNN*Coupling and Chiral Symmetry

Meson-baryon couplings between positive and negative parity baryons are investigated using two-point correlation functions in the soft meson limit. We find that the $\pi {\mathrm{NN}}^{*}$ coupling vanishes due to chiral symmetry, while the $\eta {\mathrm{NN}}^{*}$ coupling remains finite. We perform an analysis based on the algebraic method for SU (2) and SU (3) chiral symmetry, and find that baryon axial charges play an essential role for vanishing coupling constants.