# Consistency of Gauged Two Higgs Doublet Model: Gauge Sector

## TL;DR

This paper analyzes constraints on the gauge sector parameters of the gauged two Higgs doublet model using data from LEP, LHC, and projected CEPC sensitivities, clarifying the role of the Stueckelberg mass.

## Contribution

It provides the first comprehensive analysis of gauge sector constraints in the gauged two Higgs doublet model using current and future collider data.

## Key findings

- Constraints on new gauge parameters from LEP and LHC data
- Projected sensitivities of CEPC on model parameters
- Clarification on the zero Stueckelberg mass for hypercharge

## Abstract

We study the constraints on the new parameters in the gauge sector of gauged two Higgs doublet model using the electroweak precision test data collected from the Large Electron Positron Collider (LEP) at and off the Z-pole as well as the current Drell-Yan and high-mass dilepton resonance data from the Large Hadron Collider (LHC). Impacts on the new parameters by the projected sensitivities of various electroweak observables at the Circular Electron Positron Collider (CEPC) proposed to be built in China are also discussed. We also clarify why the St\"{u}eckelberg mass $M_Y$ for the hypercharge $U(1)_Y$ is set to be zero in the model by showing that it would otherwise lead to the violation of the standard charge assignments for the elementary quarks and leptons.