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

Abstract 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, R b ( μ ) ≡ σ ( b ¯ b ) / σ ( μ + μ − ) and the left–right asymmetry from the standard model are predicted.