The Hades time-of-flight wall

In the framework of the High Acceptance DiElectron Spectrometer collaboration a Time-of-Flight wall subdetector has been developed. In order to efficiently select rare events with dilepton pairs produced in the nuclear matter, in a high hadron multiplicity environment, such a wall must be able to resolve electrons from pions up to 0.5 GeV/c and from protons up to 2 GeV/c. The short flight path of about 2 m requires a time resolution better than 150 ps, while impact position and multiplicity measurements need adequate granularity. These requirements have been fulfilled by employing scintillator rods read-out at both ends by photomultipliers. (C) 2002 Elsevier Science B.V. All rights reserved.