Search strategies for the exotic decays of the Higgs boson into two photons plus missing energy at the LHC

In this study, we devise a search strategy for the exotic decay of the 125 GeV Higgs boson in the $\gamma\gamma$+missing energy final state. The studied final state comes in two different topologies: resonant and non-resonant. In the resonant case, the Higgs decays into two scalars, one being undetected and the other decaying resonantly into two photons. In the non-resonant case, based on low scale SUSY breaking models, the Higgs decays into two neutralinos, each subsequently decaying into a photon and a gravitino. We estimate the sensitivity of these searches using a DELPHES detector simulation, and targeting $100$ fb$^{-1}$ of $\sqrt{s}=14$ TeV $pp$ data from the LHC.