Test results of a high precision cathode strip chamber based on plastic streamer tubes

We have designed, built, and tested a cathode strip chamber constructed with plastic streamer tubes and printed circuit strip boards produced by industry. The prototype consists of 3 identical layers, each with an area of 50 cm × 100 cm. The prototype was tested in cosmic rays at the Texas Test Rig and a 190 GeV muon beam at CERN. A spatial resolution of 45 ± 3 μm was obtained in cosmic rays, with comparable result (53 ± 1 μm) in the muon beam. The resolution is limited by amplifier noise in the charge measurement, not by intrinsic factors. We studied the dependence of the spatial resolution on the incident angle of the muon, and found good agreement with theoretical expectation. The prototype was tested with two gas mixtures, one flammable and the other nonflammable. We found no dependence of the resolution on the gas mixture, if resolutions are compared at the same pulse height.