The Barrel DIRC detector of PANDA

摘要

The PANDA experiment is one of the four large experiments being built at FAIR in Darmstadt. It will use a cooled antiproton beam on a fixed target within the momentum range of 1.5 to 15 GeV/c to address questions of strong QCD, where the coupling constant alpha(s) greater than or similar to 0.3. The luminosity of up to 2.10(32) cm(-2) s(-1) and the momentum resolution of the antiproton beam down to Delta p/p = 4.10(-5) allows for high precision spectroscopy, especially for rare reaction processes. Above the production threshold for open charm mesons the production of kaons plays an important role for identifying the reaction. The DIRC principle allows for a compact particle identification for charged particles in a hermetic detector, limited in size by the electromagnetic lead tungstate calorimeter. The Barrel DIRC in the target spectrometer covers polar angles between 22 degrees and 140 degrees and will achieve a pion-kaon separation of 3 standard deviations up to 3.5 GeV/c. Here, results of a test beam are shown for a single radiator bar coupled to a prism with 33 degrees opening angle, both made from synthetic fused silica read out with a photon detector array with 768 pixels.