The electroweak gauge couplings in SO(5) x U(1) gauge-Higgs unification

TL;DR

This paper analyzes the electroweak gauge couplings in an SO(5) x U(1) gauge-Higgs unification model within warped space, showing tiny deviations from the Standard Model and specific large deviations for top quark couplings.

Contribution

It provides a detailed calculation of gauge couplings in a gauge-Higgs unification model, demonstrating small deviations and anomaly freedom, with specific predictions for top quark interactions.

Findings

Deviations in gauge couplings are less than 1% except for the top quark.

The model is free from 4D anomalies.

Top quark couplings deviate significantly, up to 18%."],

Abstract

The electroweak currents of quarks and leptons in the $SO(5) \times U(1)$ gauge-Higgs unification model in the Randall-Sundrum warped space are determined. The 4D gauge couplings deviate from those in the standard model and the weak universality is slightly violated. It is shown that the model is free from 4D anomalies and the deviations of the gauge couplings are tiny, less than 1% except for the top quark. The $Zt_L \bar t_L$, $Zt_R \bar t_R$, $Zb_L \bar b_L$ and $Zb_R \bar b_R$ couplings deviate from those in the standard model by -7%, 18%, 0.3% and 0.9% with the warp factor $z_L = 10^{15}$, respectively. The violation of the $\mu$-$e$, $\tau$-$e$ and $t$-$e$ universality in the charged current interactions is ${\cal O}(10^{-8})$, ${\cal O}(10^{-6})$ and 2.3%, respectively.