Prototype of a DIRC-barrel for the P̄ANDA Experiment

The P̄ANDA Experiment will be one of the large experiments of the future FAIR facility. The physics program requires a good kaon/pion-separation. To achieve this goal, three Cherenkov detectors are forseen. Around the interaction point a DIRC-barrel is planned with a readout-box inside the magnetic field. A radiator quality test is shown to point out the importance of the knowledge of the radiator surface roughness. The precision of the roughness determination itself is better than 2 Å. Furthermore the first prototype of a DIRC-barrel is presented in detail. The focussing readout is realized by a lens, attached at the end of the radiator. As photon detectors micro-channel plate PMTs are used to fulfill the requirement of an magnetic-insensitive detection. Finally preliminary results of a recent test with 2.3 GeV protons show the successful measurement of Cherenkov ring fragments in the expected region.