Further studies on the gain properties of a Gas Electron Multiplier with a Micro-Induction Gap Amplifying Structure (GEM-MIGAS) aimed at low-energy X-ray detection

Abstract

A Gas Electron Multiplier with Micro-Induction Gap Amplifying Structure (GEM-MIGAS) is formed when the induction gap of the GEM is set between 50 and 100 [mu]m using kapton pillars spaced at regular intervals. This configuration combines the properties of a GEM and Micromegas, allowing operation in tandem to generate high charge gains. We measured the essential operational parameters of this system using argon-isobutane (IB) and helium-IB gas mixtures. The present short induction gap GEM was able to achieve effective gains exceeding 2×104 using argon-IB and 105 using helium-IB mixtures. In view of the high gains achieved, particularly when using helium-based gas mixtures, these studies confirmed the possibility of using the present system for high-performance sub-keV X-ray detection.