Beam Test Results for ATLAS Muon Micromegas

MicroMegas (MicroMEsh GAseous Structure) technology is a promising candidate to replace the ATLAS muon tracking and trigger chambers in the end-cap inner layer and in the highest rapidity region of the middle layer for a future Super-LHC version of the experiment. A small prototype was built and evaluated in a beam test performed at the CERN H6 in November 2007. Some preliminary results on the performance are presented.