Performance of the ATLAS Electromagnetic Calorimeter

Data-taking at the CERN Large Hadron Collider should begin in
2008. Experiments collecting the results of the proton-proton
collisions at an unprecedented 14 TeV center-of-mass energy face a
challenging environment. For example, the calorimeters at the LHC must
operate well with a very short time between beam crossings (25 ns) and
large numbers of charged particles per event (over 1000, at design
luminosity). To search for new physical processes and make precise
measurements, the electromagnetic calorimeters need to have excellent
energy resolution over a wide range, from tens of MeV per particle to a 
few TeV. In this talk, I will focus on the ATLAS electromagnetic calorimeter, 
a lead-liquid argon sampling calorimeter with over 160,000 channels. The 
detector will be described, with emphasis on the read-out electronics, 
commissioning, and calibration.