Micromegas (Micro Mesh Gas Detectors) are micro pattern gaseous detectors, that show a high position resolution due to a readout strip pitch of
250 to 500 micrometers. Charged particles ionize the detector gas, usually consisting of argon and carbon-dioxide. Electrons from the ionization
process are amplified in an avalanche between a fine micro mesh and the readout strips. Due to the fast evacuation of positive ions within only 100 ns
the detector is intrinsically high-rate capable.
The group investigates fundamental processes within the detector such as signal formation, gas amplification processes and discharge properties. Furthermore
detector properties such as spatial and temporal resolution, energy resolution and efficiency to charged particles, photons and neutrons are investigated.
Novel discharge-sustaining readout structures, like the Floating Strip Micromegas, as well high square meter sized, high-precision stiffened readout panels
are constructed. We are working with detectors with active areas between several square centimeters to one square meter.
GEM (Gas Electron Multiplier) detectors use copper-clad Kapton foil with etched holes for gas amplification. Since it is easily possible to stack up to
three GEM foils, these detectors can be operated very stably at high gain. The spatial resolution of the detector is only limited by the hole distance to
about 100 micrometers.
Currently this group is working on photon detection with GEM detectors.
