Measurement of photon production cross sections with the ATLAS detector

The production of prompt isolated photons at hadron colliders provides a stringent test of perturbative QCD and can be used to probe the gluon density function of the proton. The ATLAS collaboration has performed precise measurements of the inclusive production of isolated prompt photons in 20.3 /fb of data collected at a center-of-mass energy of 8TeV and in 6.4 /pb of data collected at a center-of-mass energy of 13TeV, differential in both rapidity and the photon transverse momentum. The measurements are compared with state-of-the-art theory predictions at NLO in QCD and with predictions of several MC generators.