EFFECTS OF AN ANOMALOUS ZWW VERTEX ON Z DECAYS

We consider the effects of an anomalous quadrupole moment of the W on the Z0 branching ratios and asymmetries at the CERN e+e- collider LEP. Stringent experimental constraints from the parameter are evaded if. We therefore choose a scheme based on a custodial global SU(2)weak symmetry, implemented with the W-dominance mechanism such that 1 is enforced. With the expected accuracy at LEP, we find that, for the scale of new physics 1 TeV, a limit 0.34 can be obtained for this coupling. This is as good a limit as can be set at LEP 200. © 1990 The American Physical Society.