Singlet Scalar Resonances and the Diphoton Excess

Understand

ATLAS and CMS recently released the first results of searches for diphoton resonances in 13 TeV data, revealing a modest excess at an invariant mass of approximately 750 GeV.

• We find that it is generically possible that a singlet scalar resonance is the origin of the excess while avoiding all other constraints.
• We highlight some of the implications of this model and how compatible it is with certain features of the experimental results.
• In particular, we find that the very large total width of the excess is difficult to explain with loop-level decays alone, pointing to other interesting bounds and signals if this feature of the data persists.