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 violation in K^0 decays. The electromagnetic calorimeter, EmC, is a most demanding element of the detector. Two prototypes of the EmC (one for the barrel and one for the end-cap region) have been built at Frascati and tested at PSI (Switzerland) using beams of electrons, muons and pions of 40 to 290 MeV/c momentum, and at the Frascati LADON facility using photons of 20 to 80 MeV. We observe excellent linearity from 20 to 290 MeV. The energy resolution is σ(E)/E ≈4.4% √(E[GeV]) and the time resolution is ≈34ps/√(E[GeV]). We found little dipendence on incidence angle and entry position. We also determined that some π/μ identification is possible.