Search for dark matter at [equation] in final states containing an energetic photon and large missing transverse momentum with the ATLAS detector

摘要

Results of a search for physics beyond the Standard Model in events containing an energetic photon and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. As the number of events observed in data, corresponding to an integrated luminosity of 36.1?fb(^{-1})? of proton–proton collisions at a centre-of-mass energy of (13~mathrm{TeV}), is in agreement with the Standard Model expectations, model-independent limits are set on the fiducial cross section for the production of events in this final state. Exclusion limits are also placed in models where dark-matter candidates are pair-produced. For dark-matter production via an axial-vector or a vector mediator in the s-channel, this search excludes mediator masses below 750–(1200~mathrm{GeV}) for dark-matter candidate masses below 230–(480~mathrm{GeV}) at 95% confidence level, depending on the couplings. In an effective theory of dark-matter production, the limits restrict the value of the suppression scale (M_{*}) to be above (790~mathrm{GeV}) at 95% confidence level. A limit is also reported on the production of a high-mass scalar resonance by processes beyond the Standard Model, in which the resonance decays to (Zgamma ) and the Z boson subsequently decays into neutrinos.