A Large GEM-TPC Prototype Detector for anda

Abstract The PANDA spectrometer will be a state of the art universal detector for strong interaction studies at the High-Energy Storage Ring (HESR) in the future international Facility for Anti-proton and Ion Research (FAIR) at GSI, Darmstadt. The detector is designed to take advantage of the extraordinary physics potential which will be available utilizing high intensity, phase space cooled anti-proton beams. This facility will provide a cooled anti-proton beam −2 with momenta of 1.5-15 GeV/c, a maximal luminosity of 2×10 32 cms −1 that translates into 2×10 7 pp annihilations per second. A GEM based Time Projection Chamber (TPC) was one of the central tracker candidates for the PANDA experiment. To check the feasibility of such a detector system, a large prototype GEM-TPC was built and tested inside the FOPI Spectrometer at GSI. A set of three Gas Electron Multiplier (GEM) foils were used as amplification stage instead of Multi Wire Proportional Chambers. In this report, the design, construction, characterization of the prototype-detector system will be discussed in detail along with the results of recent beam tests.