Performance of MICROMEGAS with preamplification at high intensity hadron beams

We present systematic studies of efficiency-rate characteristics of the MICROMEGAS detector in high-intensity hadron beams. The discharge probability has been studied as a function of the gain for several gas mixtures. Using a full tracking system of several MICROMEGAS chambers we measured simultaneously the gain, the efficiency, the spatial resolution and the sparking probability. We are discussing the various issues, with single and double amplification, for the use of this detector in future high-rate hadron accelerators.