Pair Production of Higgs Boson in G2HDM at the LHC

TL;DR

This paper investigates Higgs pair production at the LHC within the Gauged Two Higgs Doublet Model, highlighting how new scalars and dark matter considerations influence production rates and potential signals beyond the Standard Model.

Contribution

It provides a detailed analysis of Higgs pair production in G2HDM, incorporating dark matter constraints and exploring the model's distinctive signatures at the LHC.

Findings

Higgs pair production can be significantly enhanced in G2HDM.

Dark matter relic density limits the extent of enhancement.

Distinguishing new scalar signals from the SM remains challenging.

Abstract

Pair production of Higgs boson at the Large Hadron Collider (LHC) is known to be important for the determination of Higgs boson self-coupling and the probe of new physics beyond the Standard Model (SM), especially the existence of new fundamental scalar boson. In this paper we study in detail the Higgs pair production at the LHC in a well-motivated model, the Gauged Two Higgs Doublet Model (G2HDM) in which the two Higgs doublets are properly embedded into a gauged $SU(2)_H$ and a dark matter candidate emerges naturally due to the gauge symmetry. Besides the deviations of Higgs couplings from the SM predictions, the existence of new scalars could enhance the production cross section of Higgs boson pair at the LHC significantly. However, when we take into account the relic density of dark matter and the null result in its direct search, only moderate enhancement can be maintained. We also comment on the capability of distinguishing the signal of a new generic scalar from the SM at the LHC, assuming the Higgs pair production cross sections are the same.