Interpreting 750 GeV Diphoton Resonance in the NMSSM with Vector-like Particles

Abstract

In this work, we explain the recent observed 750 GeV diphoton resonance in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) by introducing vector-like chiral superfields. Such an extension is well motivated from the top-down view since some grand unified theories usually predict the existence of singlet scalars and vector-like particles at weak scale. In our model, the 750 GeV resonance can be interpreted as two nearly degenerate singlet-like Higgs bosons (mh2 ≈ ma1 ≈ 750 GeV). The decays of h2/a1 → are dominated by the vector-like squarks with large mixing, which can also enhance the production cross section of gg → h2/a1. Under the constraints from the Higgs data and dark matter detection, we scan the parameter space and find that such a model can successfully accounts for the diphoton excess.