Higgs decay to dark matter in low energy SUSY: is it detectable at the LHC ?

TL;DR

This paper investigates the potential for detecting Higgs decays into dark matter particles within low energy SUSY models at the LHC, focusing on the NMSSM and nMSSM where such decays could be observable.

Contribution

It provides a comparative analysis of Higgs decay to dark matter in MSSM, NMSSM, and nMSSM, highlighting the conditions under which these decays are detectable at the LHC.

Findings

Higgs decay to dark matter in MSSM is undetectable at the LHC.

In NMSSM and nMSSM, the decay branching ratio can be large enough for detection.

Detection prospects depend on the specific SUSY model and parameter space constraints.

Abstract

Due to the limited statistics so far accumulated in the Higgs boson search at the LHC, the Higgs boson property has not yet been tightly constrained and it is still allowed for the Higgs boson to decay invisibly to dark matter with a sizable branching ratio. In this work, we examine the Higgs decay to neutralino dark matter in low energy SUSY by considering three different models: the minimal supersymmetric standard model (MSSM), the next-to-minimal supersymmetric standard models (NMSSM) and the nearly minimal supersymmetric standard model (nMSSM). Under current experimental constraints at 2-sigma level (including the muon g-2 and the dark matter relic density), we scan over the parameter space of each model. Then in the allowed parameter space we calculate the branching ratio of the SM-like Higgs decay to neutralino dark matter and examine its observability at the LHC by considering three production channels: the weak boson fusion VV->h, the associated production with a Z-boson pp->hZ+X or a pair of top quarks pp->htt_bar+X. We find that in the MSSM such a decay is far below the detectable level; while in both the NMSSM and nMSSM the decay branching ratio can be large enough to be observable at the LHC.