ATLAS Measurements of Isolated Photon Cross-Sections

This document presents measurements of the cross-sections for the inclusive production of isolated prompt photons and di-photon events in proton-proton collisions at a centre-of-mass energy root s = 7 TeV, performed by the ATLAS experiment at the LHC. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Residual background in the selected sample is estimated from data based on the observed distribution of the transverse isolation energy in a narrow cone around the photon candidate. The results are compared to predictions from next-to-leading order perturbative QCD calculations.