Search for new phenomena in final states with photons, jets and missing transverse momentum in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

A search for new phenomena has been performed in final states with at least one isolated high momentum photon, jets and missing transverse momentum in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13$ TeV. The data, collected by the ATLAS experiment at the CERN LHC, correspond to an integrated luminosity of 139 fb$^{-1}$. The experimental results are interpreted in a supersymmetric model in which pair-produced gluinos decay to neutralinos, which in turn decay to a gravitino, at least one photon, and jets. No significant deviations from the predictions of the Standard Model are observed, and 95% confidence-level upper limits are set on the masses of the gluinos, neutralinos and the visible cross section due to physics beyond the Standard Model.