Estudo de detectores a gás do tipo GEM e Thick-GEM usando técnica de localização espacial por linhas de retardo e eletrodo x&y

Abstract

This work presents the initial results of studies on gas detectors of the GEM (Gas Electron Multiplier) and THGEM (Thick-Gas Electron Multiplier) types, developed at the Detection System Laboratory of the Brazilian Center for Physics Research. The study aims to develop detectors capable of acquiring high-quality images, with a focus on Xray diffraction applications. THGEM devices with reduced thicknesses of 0.2 mm were fabricated, varying hole diameters and distances, and tested with gas mixtures of Ar/C2H6 (75/25) and Ar/CO2 (70/30) at atmospheric pressure, using 5.9 keV X-ray radiation. The double-THGEM and triple-GEM detectors demonstrated high gains, on the order of 104 for THGEM and 105 for GEM, as a function of the applied high voltage, in addition to good stability and efficient electron transport. The discrete delay line, consisting of 44 cells, was characterized in terms of delay and impedance, showing an efficient response for fast pulses (below 10 ns) and signals induced on the X&Y anode. It was concluded that the developed detectors performed satisfactorily, proving to be viable for use in X-ray diffraction studies, although geometric improvements are needed to reduce electron loss and optimize performance. These results indicate that GEM and Thick-GEM Technologies have great potential for advancing X-ray detection in material research.