Di-photon Higgs signal at the LHC: a comparative study for different supersymmetric models

TL;DR

This study compares the di-photon Higgs signal at the LHC across three supersymmetric models, revealing how each model predicts different signal strengths under current constraints, with potential enhancements in NMSSM.

Contribution

It provides a comparative analysis of the di-photon Higgs signal in MSSM, NMSSM, and nMSSM, highlighting the possible signal enhancements and suppressions in each model.

Findings

nMSSM always suppresses the signal

MSSM mostly suppresses, but can enhance slightly

NMSSM can both enhance and suppress, with up to 7-fold increase

Abstract

As the most important discovery channel for a light Higgs boson at the LHC, the di-photon signal $gg->h->\gamma\gamma$ is sensitive to underlying physics. In this work we investigate such a signal in a comparative way by considering three different supersymmetric models, namely the minimal supersymmetric standard model (MSSM), the next-to-minimal supersymmetric standard model (NMSSM) and the nearly minimal supersymmetric standard model (nMSSM). Under the current collider and cosmological constraints we scan over the parameter space and obtain the following observation in the allowed parameter space: (i) In the nMSSM the signal rate is always suppressed; (ii) In the MSSM the signal rate is suppressed in most cases, but in a tiny corner of the parameter space it can be enhanced (maximally by a factor of 2); (iii) In the NMSSM the signal rate can be enhanced or suppressed depending on the parameter space, and the enhancement factor can be as large as 7.