Optimization of the resolution of a track drift chamber (TPC)

In the framework of this diploma thesis it was studied, how the position resolution of a TPC can be improved. For this first properties like electron drift velocity as well transverse and longitudinal diffusion of different gases in a test TPC were determined. Starting from the measurement results it is possible, to select chamber gases with suitable drift velocity and low diffusion and to improve by this the position resolution of a TPC. The second essential point of approach for the improvement of the position resolution of a TPC was the variation of the TPC geometry. Here the pad width, the gap distance, and the sampling frequency was varied and the influence on the resolution studied. The essential result hereby was the development of a TPC with a gap distance of 1 mm, which reduced the pad response width to 1.4 mm and by this contributed to a distinct improvement of the position resolution. In a last step a gas microstrip chamber with TPC pad readout was designed, in which the amplification wire planes of the TPC were replaced by a microstrip structure on a glass substrae. Hereby the proof-of-principle of such a facility was brought and first measurements on the position resolution and on the time behaviour of the gas amplification performed. Looking out to the future further measurements with this facility, like for example variation of the substrate material, the substrate thickness, or the manufacturing process of the microstrip structure for the improvement of the time stability of the gas amplification and the position resolution would be desirable. (HSI)