Experimental HEP Seminar

ATLAS Standard Model Photon Cross Section Results

Mark Stockton

McGill University

Cross section measurements of the production of prompt photons are ideal tests of perturbative QCD. Presented here are the results from the ATLAS collaboration based on the data collected in 2010 at a centre-of-mass energy of 7 TeV. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Any 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 along with showing the impact on the gluon distribution in the proton.