摘要
A new anomaly-free gauged U(1) lepton-number model is studied. Two Standard Model (SM) lepton generations acquire the same but oppositive-sign U(1) charges, while four exotic chiral leptons cancel the anomalies of the remaining lepton family. We discuss a simplified case which has the universal Yukawa couplings. It agrees with all the experimental constraints and predicts me, mμ mτ, and the latter is of the electroweak scale. Due to the interference between the SM and U(1) gauge interactions, this model robustly predicts that e, μ, τ have distinctive forward-backward asymmetries at the e+e- colliders. It can be searched for at the e+e- machine with ∼TeV center-of-mass energy and an integrated luminosity ∼ab-1.