Search for Extra Dimensions in the Diphoton Channel using 4.9/fb of Proton-Proton Collisions recorded at 7 TeV with the ATLAS Detector

We present a search for extra dimensions in the diphoton final state with the ATLAS detector. The analysis uses an integrated luminosity of 4,91 inverse femtobarn of 7 TeV proton-proton collisions, collected during 2011. No excess is observed above the Standard Model background expectation. A lower limit of 0.89 (2.04) GeV at 95% CL is set on the lightest Randall-Sundrum graviton mass, for a coupling value of 0.01 (0.1). In the ADD large extra dimension scenario, lower limits of between 2.38 and 3.87 TeV at 95% CL are set on the fundamental Planck scale, depending on the number of extra dimensions and the theoretical formalism used.