Rate and gain limitations of MSGCs and MGCs combined with GEM and other preamplification structures

Abstract

We have studied the rate and gain limits of diamond-coated Microstrip Gas Counters (MSGCs) and Micro-Gap Counters (MGCs) when combined with various preamplification structures: Gas Electron Multiplier (GEM), Parallel-Plate Avalanche Chamber (PPAC) or a MICROMEGAS-type structure. Measurements were done both with X-rays and alpha particles with various detector geometries and in different gas mixtures at pressures from 0.05 to 10 atm.