Simulation studies of the HADES first level trigger. Part 1: Performance in heavy ion induced reactions

The first level trigger of the HADES spectrometer is studied for the heavy-ion collision systems Au+Au and Ne+Ne. The trigger efficiency for central events is given in dependence of the imposed charged particle multiplicity condition. The timing properties of the trigger signal are described. The losses due to deadtime are specified. Finally, the first level trigger rate is reported.