PN423 3 March 2000 Z Boson Pair Production in e

Abstract

A study of Z boson pair production in e e - annihilation at center-of-mass energies above 190 GeV using the OPAL detector at LEP is reported. Final states containing only leptons, (# # - and # - ##), quark and lepton pairs, (qq# # - , qq##) and only quarks (qqqq) have been studied. In all states with at least one Z boson decaying hadronically, qq and bb final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. The Z-pair cross-section measurements are which are consistent with the Standard Model prediction. Limits on anomalous ZZ# and ZZZ couplings are derived