Simulations of Multi-layer GEM Systems from Single to Quadruple GEMs

We present comparative simulation results for single, double, and triple layer Gas Electron Multiplier (GEM) Gas Pixel Detector (GPD) systems, along with some preliminary quadruple layer results, using Garfield++ and ANSYS field solver. With a multi-GEM layer structure, of up to 5 layers, a very high effective gain (up to $$10^{6}$$ in some gases) can be attained with each GEM layer working at an individually much lower gain thus avoiding discharge problems - this is the major advantage of GEM technology. We compare our results with those of published experiments and simulations.