Bonn 2010 – wissenschaftliches Programm
HK 36.88: Poster
Mittwoch, 17. März 2010, 14:00–16:00, HG Aula
Triple-GEM Detector for Readout of a 300 mm Diameter TPC — •Francesco Cusanno and Xiaodong Zhang — TUM, Garching b. München, Germany
The amplification of the primary charge in a Time Projection Chamber (TPC) is usually performed using MWPC. The use of GEM foils with asymmetric field configurations offers the possibility to avoid gating, needed in MWPC to prevent the backdrift of ions from the amplification stage to the drift volume. This way, a continuous-mode TPC may be realized, as it would be required for the central tracker of the PANDA experiment at FAIR. A medium-size GEM-TPC prototype with a diameter of 300 mm and a drift length of 702 mm, currently under construction, will be tested inside the FOPI spectrometer at GSI. The prototype of the readout stage, based on triple-GEM chamber, to be used for the charge amplification and the readout padplane consisting of 10680 hexagonal pads of 1.5 mm radius, has been built and is under testing at T. U. München. The GEM-foils have an active area of 300 mm diameter and a central dead area of 105 mm diameter in order to fit the TPC geometry. The foils are sectorized on one side in eight parts, supplied with individual HV lines. For the readout of the signals a front-end electronics based on the AFTER/T2K chip has been used. A Detailed description of the detector as well as results of the tests with cosmics rays, X-ray source and β− source will be reported.
This work has been supported by Excellence Cluster ’Universe’ and Helmoltz Gesellschaft