Genuine NMSSM deviations in the 125 GeV Higgs boson decays

TL;DR

This paper investigates unique deviations in the 125 GeV Higgs boson decays within the NMSSM, identifying specific patterns and correlations that could hint at the presence of a singlet Higgs boson and its properties.

Contribution

It provides a comprehensive analysis of genuine NMSSM deviations, including a novel parameter space scanning method and the identification of three distinct deviation regions with characteristic correlation patterns.

Findings

Three regions with genuine NMSSM deviations identified

Negative and positive correlation patterns between fermionic and bosonic channels found

Correlation signs depend on the mass difference between Higgs states

Abstract

In Supersymmetry deviations from the SM signal strengths of the 125 GeV Higgs boson can occur, because of possible SUSY contributions in diagrams with loops, which leads to different deviations in signal strengths for processes with and without loop diagrams. In the Next-to Minimal Supersymmetric Standard Model (NMSSM) additional deviations may occur, because of the mixing with the additional singlet-like Higgs boson and/or additional decays into pairs of light particles, like neutralinos, pseudo-scalar Higgs bosons or singlet-like Higgs bosons. In this paper we study these "genuine" NMSSM deviations in detail to check not only their possible size, but also look for correlations or anti-correlations with respect to other channels in the hope to find specific patterns in the deviations as for the SUSY contributions, which occur predominantly in processes including loops in the diagrams. The whole NMSSM parameter space is sampled in a deterministic way. The novel scanning method is discussed in detail in the Appendix. We found three different regions with "genuine" NMSSM deviations, which are largely independent of the production mode. What was surprising: some regions show negativ correlations between final states with fermions and bosons meaning if the signal strengths for fermions decrease the signal strengths for bosonic final states increase, while other regions show positive correlations. The sign of the correlations is a strong function of the mass difference between the observed 125 GeV Higgs boson and the Higgs singlet, so looking for correlations could give useful hints about the existence and mass of the singlet Higgs boson. The features of these "genuine" NMSSM effects have been investigated in representative benchmark points for each of the three regions where a single effect is dominant. These benchmark points have been detailed in the Appendix.