Measurement of the inclusive isolated prompt photon cross-section in proton-proton collisions at sqrt(s) = 8 TeV with the ATLAS detector.

Differential cross-section measurements of the inclusive production of isolated prompt photons in proton-proton collisions at a centre-of-mass energy sqrt(s) = 8 TeV are presented. The measurements cover the pseudorapidity regions |eta| < 1.37 and 1.56 ≤ |eta| < 2.37 in the photon transverse energy range 25 GeV < E_T_γ < 1500 GeV. Results are based on a data sample corresponding to an integrated luminosity of 20.2 fb^−1, collected with the ATLAS detector at the Large Hadron Collider in 2012. Photon candidates are identified by combining information from the ATLAS calorimeters and inner tracker. The signal yield is measured using a data-driven technique. The measured differential cross-section values are compared to leading order and next- to-leading order perturbative QCD calculations and found to be in good agreement over ten orders of magnitude.