CONSTRUCTION AND PERFORMANCE OF THE LEAD-SCINTILLATING FIBER CALORIMETER PROTOTYPES FOR THE KLOE DETECTOR

The KLOE detector is designed primarily for the study of direct CP vio lation in KO decays. The electromagnetic calorimeter, EmC, is a most d emanding element of the detector. Two prototypes of the EmC (one for t he barrel and one for the end-cap region) have been built at Frascati and tested at PSI (Switzerland) using beams of electrons, muons and pi ons of 40 to 290 MeV/e momentum, and at the Frascati LADON facility us ing photons of 20 to 80 MeV. We observe excellent linearity from 20 to 290 MeV. The energy resolution is sigma(E)/E similar to 4.4%/root E(G eV) and the time resolution is similar to 34 ps/root E(GeV). We found little dependence on incidence angle and entry position. We also deter mined that some pi/mu identification is possible.