Measurement of charge asymmetry in hadronic Z decays

A significant charge asymmetry is observed in the hadronic Z decays with the ALEPH detector at LEP. The asymmetry expressed in terms of the difference in momentum weighted charges in the two event hemispheres is measured to be −= −0.0084±0.0015 (stat.) ±0.0004 (exp. sys.). In the framework of the standard model this can be interpreted as a measurement of the effective electroweak mixing angle, sin2Ow (Mz2=0.2300±0.0034 (stat.) ±0.0010 (exp. sys.) ±0.0038 (theor. sys.) or of the ratio of the vector to axual- vector coupling costants of the electron, gvegAe=+0.073±0.024

Search for excited leptons in Z0 decay

We have looked for evidence of excited lepton production in Z0 decay observed in the ALEPH detector at LEP. We find no ℓℓγγ events and set new limits at 95% CL on ℓ∗ masses at 44.6, 44.6 and 41.2 GeV/c2 for respectively. Observed events in the ℓℓγ channels are consistent with radiative effects and we set limits for the first time on the coupling for ℓ∗ masses in the range up to 86 GeV/c2