Effects of flavour mixing induced by axial anomaly on the quark condensates and meson spectra

Effects of the UA(1) anomaly as well as the explicit breaking of SU-f(3) symmetry are analyzed both for the quark condensates and meson spectra using a QCD motivated effective lagrangian. After developing a systematic way to treat the instanton induced six-Fermi interaction representing the anomaly, we determine the strength of the anomaly term so as to reproduce meson masses and the pion decay constant. The spectra of the Nambu-Goldstone (NG) bosons (π, K, η) and the would-be NG boson (η') are evaluated without recource to the chiral perturbations. The anti ss contents of nucleons arising from the flavour mixing is also evaluated. (orig.)