Long term stability study of triple GEM detector using different Argon based gas mixtures: an update

TL;DR

This study evaluates the long-term stability of a triple GEM detector with different Argon-based gas mixtures under high-rate X-ray irradiation, focusing on gain, energy resolution, and environmental effects.

Contribution

It provides new stability data for Ar/CO2 (80:20) and (90:10) mixtures, expanding previous work on Ar/CO2 (70:30) in GEM detectors.

Findings

Stable operation observed for all gas mixtures tested.

Environmental factors like temperature and pressure influence detector performance.

The setup reduces complexity and cost by using the same source for irradiation and spectra monitoring.

Abstract

The long-term stability in terms of gain and energy resolution of a prototype triple Gas Electron Multiplier (GEM) detector has been investigated with high rate X-ray irradiation. Premixed Ar/CO2 (80:20) and (90:10) gases have been used for this stability study. A strong Fe55 X-ray source is used to irradiate the chamber. The uniqueness of this work is that the same source has been used to irradiate the GEM prototype and also to monitor the spectra. This arrangement is important since it reduces the mechanical complexity of using an X-ray generator as well as the cost of the setup. A small area of the chamber is exposed continuously to the X-ray for the entire duration of the operation. The effect of temperature and pressure on the gain and energy resolution is monitored. The result of the long-term stability test for a triple GEM detector using Ar/CO2 (70:30) gas mixture has been reported earlier [1]. The results with Ar/CO2 (80:20) and (90:10) gas mixtures for the same chamber are presented in this article.