Search for scalar diphoton resonances in the mass range 65-600 GeV with the ATLAS detector in pp collision data at $\sqrt{s}$ = 8 TeV

A search for scalar particles decaying via narrow resonances into two photons in the mass range 65--600 GeV is performed using 20 $fb^{-1}$ of $pp$ collision data collected with the ATLAS detector at $\sqrt{s}$ = 8 TeV at the Large Hadron Collider. The Higgs boson of mass 125.9 GeV is treated as a background. No significant evidence for an additional signal is observed. The result is presented as a model-independent limit at the 95\% confidence level on the production cross-section times branching fraction into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches.