Extended Higgs boson sectors, effective field theory, and Higgs boson phenomenology

Anisha Anisha,Upalaparna Banerjee,Christoph Englert,Joydeep Chakrabortty,Michael Spannowsky

doi:10.1103/physrevd.103.096009

Anisha Anisha, Upalaparna Banerjee + Show 3 more

Open Access

https://doi.org/10.1103/physrevd.103.096009

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Abstract

We consider the phenomenological implications of charged scalar extensions of the SM Higgs sector in addition to EFT couplings of this new state to SM matter. We perform a detailed investigation of modifications of loop-induced decays of the 125 GeV Higgs boson, which receives corrections from the propagating charged scalars alongside one-loop EFT operator insertions and demonstrate that the interplay of $H\to \gamma\gamma$ and $H\to Z\gamma$ decays can be used to clarify the additional states phenomenology in case a discovery is made in the future. In parallel, EFT interactions of the charged Higgs can lead to a decreased sensitivity to the virtual presence of charged Higgs states, which can significantly weaken the constraints that are naively expected from the precisely measured $H\to \gamma\gamma$ branching ratio. Again $H\to Z\gamma$ measurements provide complementary sensitivity that can be exploited in the future.

Highlights

The search for physics beyond the Standard Model (BSM) is the highest priority of the Large Hadron Collider (LHC) after the discovery of the Higgs boson [1,2]
While even parametrically small Yukawa couplings can lead to discoverable clean leptonic final states as mentioned above, the electroweak pair production cross section is suppressed such that the LHC will be statistically limited in a mass range Mh ≃ 500 GeV
This highlights the question of whether additional new physics that arises as a nontrivial extension of the extra scalar’s interactions can have phenomenologically relevant implications. We approach this question by means of effective field theory, i.e., we assume a mass gap between the charged BSM scalar and other states that lead to generic effective operators involving the scalar and the Standard Model fields

Summary

INTRODUCTION

The search for physics beyond the Standard Model (BSM) is the highest priority of the Large Hadron Collider (LHC) after the discovery of the Higgs boson [1,2]. To the SM providing additional propagating degrees of freedom to modify observed SM Higgs rates These states appear in many BSM Higgs sector extensions (e.g., in twoHiggs-doublet [5] or -triplet models [6]). Considering EFT operators up to dimension 6, we compute the loop-induced decays of the SM Higgs (see [7,8,9,10,11,12,13,14,15,16,17]) in this scenario to identify regions of consistency with the SM expectation (for similar analyses of electroweak observables, see, e.g., [18,19]) This highlights the possibility of nonminimal interactions of the charged Higgs as parametrized by the EFT interactions to significantly reduce the sensitivity of the naively (highly) constraining SM Higgs H → γγ decay mode.

THE MODEL

ELEMENTS OF THE CALCULATION

Constraints

Loop-induced Higgs phenomenology

CONCLUSIONS