Diphoton Signal of light pseudoscalar in NMSSM at the LHC

TL;DR

This paper investigates the potential to detect a light pseudoscalar Higgs boson in the NMSSM at the LHC via a diphoton signal, focusing on specific parameter space regions where the pseudoscalar decays to two photons.

Contribution

It presents a detailed simulation study of the diphoton signal from a light pseudoscalar Higgs in NMSSM, highlighting its detectability and distinguishing features at the LHC.

Findings

Certain parameter regions allow detectable diphoton signals for pseudoscalar masses 60-100 GeV.

Some benchmark points can be probed with 100 fb$^{-1}$ luminosity.

The channel can help differentiate NMSSM from other supersymmetric models.

Abstract

We explore the detection possibility of light pseudoscalar Higgs boson in the next-to-minimal supersymmetric Standard Model(NMSSM) at the LHC with the center of mass energy, $\sqrt{S}=13$ TeV. We focus on the parameter space which provides one of the Higgs boson as the SM-like with a mass of 125 GeV and some of the non-SM-like Higgs bosons can be light having suppressed couplings with fermions and gauge bosons due to their singlet nature. It is observed that for certain region of model parameter space, the singlet like light pseudoscalar can decay to di-photon($\gamma\gamma$) channel with a substantial branching ratio. In this study, we consider this di-photon signal of light pseudoscalar Higgs boson producing it through the chargino-neutralino production and the subsequent decay of neutralino. We consider signal consisting of two photons plus missing energy along with a lepton from the chargino decay. Performing a detailed simulation of the signal and backgrounds including detector effects, we present results for a few benchmark points corresponding to the pseudoscalar Higgs boson mass in the range 60 -100 GeV. Our studies indicate that some of the benchmark points in the parameter space can be probed with a reasonable significance for 100 fb$^{-1}$ integrated luminosity. We also conclude that exploiting this channel it is possible to distinguish the NMSSM from the other supersymmetric models.