Bhabha scattering in the gauge-Higgs unification

AbstraktAbstract

We examine effects of Z′ bosons in gauge-Higgs unification (GHU) models at e^+ e^−→e^+ e^− Bhabha scatterings. We evaluate differential cross sections in Bhabha scatterings including Z′ bosons in two types of SO(5)×U(1)×SU(3) GHU models. We find that deviations of differential cross sections in the GHU models from those in the SM can be seen at √s=250 GeV. With 80%-longitudinally polarized electron and 30%-longitudinally polarized positron beams, the left-right asymmetries in the GHU A and B models are resolved at more than 3σ at L_{int}=250 fb^{−1}. We also show that Bhabha scattering with scattering angle less than 100 mrad can be safely used as luminosity measurements at e^+ e^− colliders since the effects of Z′ bosons are well suppressed for small scattering angle. We propose a new observable which can be measured at future TeV-scale e^+ e^− linear colliders.

We examine effects of Z′ bosons in gauge-Higgs unification (GHU) models at e^+ e^−→e^+ e^− Bhabha scatterings. We evaluate differential cross sections in Bhabha scatterings including Z′ bosons in two types of SO(5)×U(1)×SU(3) GHU models. We find that deviations of differential cross sections in the GHU models from those in the SM can be seen at √s=250 GeV. With 80%-longitudinally polarized electron and 30%-longitudinally polarized positron beams, the left-right asymmetries in the GHU A and B models are resolved at more than 3σ at L_{int}=250 fb^{−1}. We also show that Bhabha scattering with scattering angle less than 100 mrad can be safely used as luminosity measurements at e^+ e^− colliders since the effects of Z′ bosons are well suppressed for small scattering angle. We propose a new observable which can be measured at future TeV-scale e^+ e^− linear colliders.