We describe comparative laboratory and beam test measurements of identical
MSGC and GEM-equipped MSGCs. Both kinds of detectors have been tested under
exactly the same conditions, using radioactive sources and muon beams. The
principal aim of this comparative study was to evaluate the operating cond
itions for the same resulting gain. Results on efficiencies and spatial res
olution are presented. Possible applications of GEM-equipped MSGCs in the L
HC environment and the R&D studies needed are discussed. (C) 1998 Elsevier
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