Studien zu den Nachweiseigenschaften des OPERA-Driftroehrenspektrometers

Within the framework of this diploma thesis the density dependent detection characteristics of the OPERA Precision Tracker are studied at a test set up with two drift tube modules. Measurements of gain, hit efficiency, spatial resolution and time{to{distance relation are presented depending on the density, anode voltage and discriminator thresholds. At a constant anode voltage the gain falls with increasing density. Therefore the hit efficiency and the spatial resolution decrease with increasing density above 1,70 kg/m 3 . Within the temperature-fluctuations of 6 K inside the LNGS, an uncertainty of the spatial resolution up to 75 m is found. Within these temperature-fluctuations the upper limit for the variation of the drift distance at a drift time of 1200 ns is about 220 m. Both effects are tolerable for the spatial resolution of the OPERA Drift Tubes.