Micromegas study for the sLHC environment

With the luminosity increase by a factor ten envisaged at the sLHC, the background (photons, neutrons, ...) and the event pile-up probability are expected to increase in proportion in the different experiments, especially in the forward regions as, for instance, the chambers of the ATLAS Muon Spectrometer. Detectors based on the Micromegas principle could be good alternatives for the detector upgrade in the sLHC framework because of a good spatial ( < 100 μm) and time (few ns) resolutions, high-rate capability, radiation hardness, good robustness and the possibility to build large areas. The aim of this study is to demonstrate that it is possible to reduce the discharge probability and intensity, and protect the electronics by using a resistive anode plane, or a segmented mesh, in a high flux hadrons environment. Several prototypes of 10 x 10 cm2, with different pitches (0.25 to 2 mm) and different resistive layers (2 to 20 MΩ/□) have been tested at CERN (120 GeV π+-SPS). Results of tests performed previously in the laboratory, during the preparation phase, are presented here along with preliminary results of the beam test.