Distinct signals of the gauge-Higgs unification in e+e− collider experiments

Effects of Kaluza-Klein excited neutral vector bosons (Z′ bosons) in the gauge-Higgs unification on e+e−→q¯q,ℓ+ℓ− cross sections are studied, particularly in future e+e− collider experiments with polarized beams. Significant deviations in the energy and polarization dependence in σ(μ+μ−), the lepton forward-backward asymmetry, Rb(μ)≡σ(b¯b)/σ(μ+μ−) and the left-right asymmetry from the standard model are predicted.