Institut de recherche sur les lois fondamentales de l'Univers

Performant identification and energy measurement of electrons and photons are required for many studies
performed at the Large Hadron Collider, among which precise studies of the Higgs boson using the
di-photon final state.
The role of the ATLAS Liquid Argon electromagnetic calorimeter in these measurements will be discussed.
The studies of its performance with pp collision data will be described, including the extraction of in-situ
calibration corrections.
The foreseen upgrades will also be presented and their impacts on the physics program summarized.