Study of sparking in Micromegas chambers

Abstract The discharge properties of Micromegas detector are studied in detail. Tests have demonstrated that the origin of discharges in hadron beams is mainly associated with nuclear interactions of the incident particle with the gas of the detector. Use of low average Z gas mixtures diminishes the spark rate. The streamer discharge model of Raether has been proved to be valid for this detector. A detector polarization which minimizes the spark energy is proposed. Gas and geometry factors improving the discharge limit are discussed.