$W$ and $Z$ Boson Pair Production at Electron-Positron Colliders in Gauge-Higgs Unification

TL;DR

This paper investigates $W$ and $Z$ boson pair production at electron-positron colliders within a gauge-Higgs unification model, finding small deviations from the Standard Model predictions that are consistent with current experimental bounds.

Contribution

It provides the first detailed analysis of $W$ and $Z$ pair production in a specific gauge-Higgs unification model, quantifying deviations from the Standard Model.

Findings

Deviations in $W^-W^+$ production cross section are 0.5% to 1.5% at 250 GeV and 0.6% to 2.2% at 500 GeV.

$ZZ$ production deviations are at most 1%.

Unitarity bounds are satisfied in the GHU model, similar to the Standard Model.

Abstract

We examine $W$ and $Z$ boson pair production processes at electron-positron collider experiments in the $SU(3)_C\times SO(5)_W\times U(1)_X$ gauge-Higgs unification (GHU) model. We find that the deviation of the total cross section for the $e^-e^+\to W^-W^+$ process from the Standard Model (SM) in the GHU model with parameter sets, which are consistent with the current experiments, is about 0.5% to 1.5% and 0.6% to 2.2% for $\sqrt{s}=250$GeV and 500GeV, respectively, depending on the initial electron and positron polarization. We find that for the $e^-e^+\to ZZ$ process the deviation from the SM in the GHU model is at most 1%. We find that unitality bound for the $e^-e^+\to W^-W^+$ process is satisfied in the GHU model as in the SM, as a consequence of the relationship among coupling constants.