Performance of the ATLAS calorimeters

The ATLAS calorimeter provides precision measurements of electrons, photons, jets and missing transverse energy produced in the LHC proton-proton collisions. High granularity liquid-argon electromagnetic and hadronic sampling calorimeters are used. An iron-scintillator hadronic calorimeter surrounds the liquid-argon detectors. Results assessing the calorimeter performance obtained using cosmic ray muons are presented. The non-uniformity of the barrel electromagnetic calorimeter response is consistent at the percent level with the simulated response. Radiative cosmic muons show that he electromagnetic shower profiles are in good agreement with the simulated ones. The response uniformity of the hadronic calorimeter compartments is at the level of 4%. The energy response shows a maximum difference among the calorimeter radial layers of 4%. The determination of the global energy scale was performed in the hadronic calorimeter with an uncertainty of ±4%.