Leptonic CP-violating asymmetry in e+e- annihilation due to Z width effects

CP-violating rate asymmetry can be generated in a process only if its amplitude possesses an absorptive part. Such an absorptive part can be provided in e+e- annihilation by the presence of a Z resonance of nonzero width. The lepton-flavor-violating CP asymmetry in the process e+e-→libarlj(bar lilj), where li are charged leptons, is discussed in several models. In a specific two-Z model, with an extra U(1) gauge group corresponding to Le-Lτ (Le,Lτ being the lepton numbers associated with the electron and the τ lepton), large and observable CP asymmetry in e+e-→τ+e-(τ-e+) is shown to be possible at energies reached at the CERN e+e- collider and SLAC Linear Collider. Various constraints coming from present experimental data have been taken into account while making this prediction