Anomalous interactions at theZ 0-pole

We study, with an effective lagrangian technique, the possible deviations from the standard model ine ⁺ e ^? collisions at theZ ⁰-pole. We consider dimension 6 anomalous interactions satisfying the fullSU(2)×U(1) gauge invariance, baryon and lepton number conservation, as well as full chiral and flavour symmetry. In this scheme, for reactions not involving the Higgs, the effects are all parametrized by modifications ofZ ⁰ partial widths into fermions. Significant anomalies, including CP violation, could only come out inZ ⁰→H ⁰γ and \(Z^0 \to H^0 f\bar f\) .