Universal Doublet-Singlet Higgs Couplings and phenomenology at the CERN Large Hadron Collider

TL;DR

This paper proposes a minimal extension to the standard model with a singlet scalar, predicting near-maximal Higgs mixing, fixed mass ratios, and standard decay modes, which can be tested at the LHC.

Contribution

It introduces a universal scalar coupling framework leading to distinctive Higgs phenomenology with specific mass and mixing predictions.

Findings

Higgs mixing is near maximal.

Mass ratio of Higgs states is approximately √3.

Predicted Higgs masses are between 114-145 GeV and 198-250 GeV.

Abstract

We consider a minimal extension of the standard model where a real, gauge singlet scalar field is added to the standard spectrum. Introducing the Ansatz of universality of scalar couplings, we are led to a scenario which has a set of very distinctive and testable predictions: (i) the mixing between the standard model Higgs and the new state is near maximal, (ii) the ratio of the two Higgs mass eigenstates is fixed ($\sim \sqrt{3}$), (iii) the decay modes of each of the two eigenstates are standard model like. We also study how electroweak precision tests constrain this scenario. We predict the lighter Higgs to lie in the range of 114 and 145 GeV, and hence the heavier one between 198 and 250 GeV. The predictions of the model can be tested at the upcoming LHC.