Test results of Gas Electron Multiplier coupled with a MSGC in October 1997
are described. Several studies have been realized in a beam of Minimum Ion
izing Particles (100 GeV/c muons): signal-to-noise curves for different GEM
amplifications and drift fields, spatial resolution, efficiency and cluste
r size. GEM acts as a simple added element with little disturbance of the s
ystem (on the electronics or no degradation of the spatial resolution). (C)
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