Phenomenology of an $SU(2)_1 \times SU(2)_2 \times U(1)_Y$ model at the LHC

TL;DR

This paper explores a minimal $SU(2)$ extension of the Standard Model at the LHC, analyzing new gauge bosons, heavy Higgs production, and potential signals with significant discovery prospects.

Contribution

It introduces a novel $SU(2)$ gauge extension with a heavy Higgs and vector-like quarks, providing bounds and collider signatures relevant for LHC searches.

Findings

New gauge coupling and boson masses constrained by electroweak data

Heavy Higgs diphoton signals can match LHC observations with proper Yukawa couplings

Potential for over 4 sigma significance in heavy Higgs diphoton plus jet channel at high luminosity

Abstract

We investigate the implications of a minimal $SU(2)$ gauge symmetry extension of the standard model at the LHC. To achieve the spontaneous symmetry breaking, a heavy Higgs doublet of the $SU(2)$ is introduced. To obtain an anomaly free model and the decays of new charged gauge bosons, we include a vector-like quark doublet. We also employ a real scalar boson to dictate the heavy Higgs production via the gluon-gluon fusion processes. It is found that the new gauge coupling and the masses of new gauge bosons can be strictly bounded by the electroweak $\rho$-parameter and dilepton resonance experiments at the LHC. It is found that due to the new charged gauge boson enhancement, the cross sections for a heavy scalar boson to diphoton channel measured by ATLAS and CMS can be easily satisfied when the values of Yukawa couplings are properly taken. Furthermore, by adopting event simulation, we find that the significance of $pp\to (\gamma \gamma)_H+{\rm jet}$, where the diphoton is from the heavy Higgs decay, can be over $4\sigma$ when the luminosity is above 60 fb$^{-1}$.