Construction and performance of the lead-scintillating fiber calorimeter prototypes for the KLOE detector

Abstract 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 ∼ 34 ps/” E (GeV). We found little dependence on incidence angle and entry position. We also determined that some π μ identification is possible.