The HADES Pre-Shower detector

The Pre-Shower detector was built for the high acceptance di-electron spectrometer to identify electrons produced in pion, proton and heavy ion-induced reactions in the 0.2<p<1.5 GeV/c momentum range. The system is composed of three layers of wire chambers interleaved with two layers of lead converters for electromagnetic shower formation. A scintillator wall is placed in front of the detector for time-of-flight measurements. The paper describes the Pre-Shower detector construction, the detector operation, the read-out electronics and its response to charged particles studied with electron, proton and heavy ion beams