Electronic calibration of the ATLAS LAr calorimeter

The Liquid Argon (LAr) calorimeter is a key detector component in the ATLAS experiment at the LHC, designed to provide precision measurements of electrons, photons, jets and missing transverse energy. A critical element in the precision measurement is the electronic calibration. In this article, the computation of the energy deposited in a cell is presented as well as the role of the different calibration constants, revealing the complex calibration scheme which has been put in place. Since the installation of the LAr calorimeter in the ATLAS cavern, the electronic calibration of the readout system has been continuously exercised in the commissioning phase. The large amount of collected calibration data allows careful studies of the stability of constants, like pedestals and pulse shapes. Thanks to the experience gained during the last two years, a calibration procedure has been put in place for the LHC running period.