Rare decays of the Z at LEP

Abstract

I discuss the preliminary results of the LEP experiments ALEPH, DELPHI, L3, and OPAL on the rare Z decays. Limits of about 105I−5 on the branching ratios are reported by most experiments. The question of excess in the ττV final state remains unsettled. From the analysis of the L3 data the ZZ′ mixing angle is confined to ±1.5° for most extensions of the Standard Model of electroweak interactions.