Characterization of microbulk detectors in argon- and neon-based mixtures

TL;DR

This paper characterizes microbulk Micromegas detectors in argon and neon mixtures, highlighting their improved uniformity, stability, and energy resolution, and analyzing gain behavior and underlying parameters.

Contribution

It presents a detailed characterization of microbulk detectors in various gas mixtures, including gain modeling and analysis of energy resolution factors.

Findings

Achieved energy resolution as low as 11% FWHM at 5.9 keV in Ar+5%iC4H10

Gain curves fitted to Rose-Korff model revealing electron mean free path and ionization threshold dependencies

Characterized detectors with different gaps in multiple gas mixtures

Abstract

A recent Micromegas manufacturing technique, so called Microbulk, has been developed, improving the uniformity and stability of this kind of detectors. Excellent energy resolutions have been obtained, reaching values as low as 11% FWHM at 5.9 keV in Ar+5%iC4H10. This detector has other advantages like its flexible structure, low material budget and high radio-purity. Two microbulk detectors with gaps of 50 and 25 um have been characterized in argon- and neon-based mixtures with ethane, isobutane and cyclohexane. The results will be presented and discussed. The gain curves have been fitted to the Rose-Korff gain model and dependences of the electron mean free path and the threshold energy for ionization have been obtained. The possible relation between these two parameters and the energy resolution will be also discussed.