Search for Scalar Diphoton Resonances in the Mass Range \(65-600\) GeV with the ATLAS Detector in \(pp\) Collision Data at \(\sqrt{s}\) = 8 \(TeV\)

Abstract

A search for scalar particles decaying via narrow resonances into two photons in the mass range \(65-600\) GeV is performed using 20.3 fb\(^{-1}\) of \(\sqrt{s}\) = 8 TeV \(pp\) collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95 % confidence level on the production cross-section of a scalar boson times branching ratio 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.