Cornering variants of the Georgi-Machacek model using Higgs precision data

Dipankar Das,Ipsita Saha

doi:10.1103/physrevd.98.095010

Abstract

We show that in the absence of trilinear terms in the scalar potential of Georgi-Machacek model, heavy charged scalars do not necessarily decouple from the $h \to \gamma \gamma$ decay amplitude. In such scenarios, measurement of the Higgs to diphoton signal strength can place stringent constraints in the parameter space. Using the projected precisions at the High Luminosity LHC (HL-LHC) and the ILC, we find that the upper bound on the triplet vacuum expectation value can be as low as 10 GeV. We also found that when combined with the theoretical constraints from perturbative unitarity and stability, such variants may be ruled out altogether.

Highlights

The discovery of a Higgs-like scalar at the Large Hadron Collider (LHC) [1,2], has initiated a deeper investigation into its origin
Using the projected precisions at the High Luminosity LHC (HL-LHC) and the ILC, we find that the upper bound on the triplet vacuum expectation value can be as low as 10 GeV
The standard model (SM) extended by a scalar triplet only, which goes by the name of Higgs triplet model (HTM) does not preserve the custodial symmetry at the tree-level

Summary

Introduction

The discovery of a Higgs-like scalar at the Large Hadron Collider (LHC) [1,2], has initiated a deeper investigation into its origin. Cornering variants of the Georgi-Machacek model using Higgs precision data Quite clearly, when combined with the lower limit on vt stemming from perturbative unitarity, we can potentially rule out the variants of GM models with M1, M2 1⁄4 0 using future Higgs precision data. We have revisited the scalar sector of the GM model in the light of Higgs precision data.

Results

Conclusion