Study of charging up effect in a triple GEM detector

The advancement of Micro Pattern Gaseous Detector technology offers us\ndifferent kinds of detectors with good spatial resolution and high rate\ncapability and the Gas Electron Multiplier (GEM) detector is one of them.\nTypically GEM is made up of a thin polyimide foil having a thickness of 50\nmicrometers with 5 micrometers copper cladding on top and bottom sides. The\npresence of polyimide changes the gain of the detector under the influence of\nexternal radiation and the phenomenon is referred to as the charging up effect.\nThe charging up effect is investigated with a double mask triple GEM detector\nprototype with Ar/CO$_2$ gas mixture in 70/30 ratio under continuous\nirradiation from a strong Fe$^{55}$ X-ray source. The detailed method of\nmeasurements and the test results are presented in this article.\n