The Diphoton and Diboson Excesses in a Left-Right Symmetric Theory of Dark Matter

Abstract

We explore the possibility that the recently reported diphoton excess at ATLAS and CMS can be accommodated within a minimal extension of a left-right symmetric model. Our setup is able to simultaneously explain the Run 2 diphoton and Run 1 diboson excesses, while providing a standard thermal freeze-out of weak-scale dark matter. In this scenario, the 750 GeV neutral right-handed Higgs triplet is responsible for the diphoton excess. Interactions of this state with the neutral and charged components of dark matter multiplets provide the dominant mechanisms for production and decay. A striking signature of this model is the additional presence of missing energy in the diphoton channel.