CP violation and Z boson decays

We present a general discussion of CP-violating effects in the following two and three body decays of the Z boson: Z → ι+ι-, Z → ι+ι-γ, where ι = e, μ, τ and Z → 2 jets, Z → 2 jets+γ, and Z → 3 jets. Experimental observables sensitive to CP violation in these decays are discussed systematically for the case that polarizations of final state particles are not observed. It is shown that the standard model predicts only extremely small CP-violating effects for the above decays. Possible CP-violating interactions beyond the standard model are parametrized in terms of a CP-odd effective Lagrangian containing coupling constants proportional to ΛCP-1 and ΛCP-2. Here ΛCP is the mass scale associated with the assumed new interactions. We give estimates of the bounds obtainable for ΛCP in experiments at LEP1. (orig.)