A measurement of the cross section for the inclusive production of isolated prompt photons in proton-proton collisions at a centre-of-mass energy of s=8 TeV is presented. The measurement covers the pseudorapidity ranges |ηγ | < 1.37 and 1.56 ≤ |ηγ | < 2.37 in the transverse energy range 25 < ETγ < 1500 GeV. The results are based on an integrated luminosity of 20.2 fb−1, recorded by the ATLAS detector at the LHC. Photon candidates are identified by combining information from the calorimeters and the inner tracker. The background is subtracted using a data-driven technique, based on the observed calorimeter shower-shape variables and the deposition of hadronic energy in a narrow cone around the photon candidate. The measured cross sections are compared with leading-order and next-to-leading order perturbative QCD calculations and are found to be in a good agreement over ten orders of magnitude.
Aad, G., Abbott, B., Abdallah, J., Abdinov, O., Abeloos, B., Aben, R., et al. (2016). Measurement of the inclusive isolated prompt photon cross section in pp collisions at s=8TeV with the ATLAS detector. JOURNAL OF HIGH ENERGY PHYSICS, 2016(8) [10.1007/JHEP08(2016)005].