Diphoton signal of the light Higgs boson in natural NMSSM

The natural Next-to-Minimal Supersymmetric Standard Model (nNMSSM) is featured by predicting one CP-even Higgs boson satisfying m(h1) less than or similar to 120 GeV and Higgsinos lighter than about 300 GeV, and consequently, the cross section for dark matter (DM)-nucleon scattering in this scenario is usually quite large. We study the diphoton signal of the light Higgs boson in nNMSSM by considering the tight constraints from the latest LUX and PandaX-II experiments, and we conclude that the optimal value of the signal rate at 8 TeV LHC is greatly reduced in comparison with earlier predictions. For example, previous studies indicated that the rate may exceed 120 fb for m(h1) similar or equal to 80 GeV, while it is at most 25 fb if the lightest neutralino in the scenario is fully responsible for the measured DM relic density. We also investigate the case of m(h1) similar or equal to 98 GeV, which is hinted by the excesses of the large electron proton collider analysis on Z (b) over bar b signal and the compact muon solenoid analysis on the diphoton signal. We conclude that nNMSSM can simultaneously explain the excesses at the 1 sigma level without violating any known constraints.