Performance of an electromagnetic liquid krypton calorimeter based on a ribbon electrode tower structure

The NA48 collaboration is preparing a new experiment at CERN aiming to study CP violation in the K-0-(K-0) over bar system with an accuracy of 2 x 10(-4) in the parameter Re(epsilon'/epsilon). Decays in two pi(0)'s will be recorded by a quasi-homogeneous liquid krypton calorimeter. A liquid krypton calorimeter has been chosen to combine good energy, position and time resolution with precise charge calibration and long-term stability. The prototype calorimeter incorporating the final design of the electrode read-out structure is presented in this paper. An energy resolution of similar or equal to 3.5%/root E with a constant term smaller than 0.5% has been obtained. The time resolution was found to be better than 300 ps above 15 GeV.