Test beam study of the Si/W calorimeter for the PHENIX forward upgrade

The Si/W calorimeter prototype for the PHENIX forward upgrade has been tested using the electron beam of various energies available from PS and SPS at CERN. The measured energy shows a good linearity and the obtained energy resolution σE/E can be parametrized as 3.8% ±22%/√(E(GeV). The energy deposition profile measured for 6 GeV electron beam features a characteristic electromagnetic shower and agrees with the Monte Carlo simulation based on GEANT4. Position and angle of the incident electron can be reconstructed from the measured energy deposition profile. The resolution of the obtained position is 2 (mm).