Performance of micro wire detector at a PSI test-beam

99-021 This note describes the behaviour of a Micro Wire Detector in a test-beam at the Paul Scherrer Institute (PSI), Switzerland. The results of the irradiation tests done with pion minus and proton/pion plus beams at intensities 2 10^4[1/mm^2 s] show no evidence of degradation of detector performance with respect to its laboratory operation parameters, previously determined with X-rays, up to an integrated charge of 150mC over the area of 12.8cm^2. The time resolution of the detector was also determined to be better than 21ns.