Production and validation of industrially produced large-sized GEM foils for the Phase-2 upgrade of the CMS muon spectrometer

Abstract

The upgrade of the CMS detector for the high luminosity LHC (HL-LHC) will include gas electron multiplier (GEM) detectors in the end-cap muon spectrometer. Due to the limited supply of large area GEM detectors, the Korean CMS (KCMS) collaboration had formed a consortium with Mecaro Co., Ltd. to serve as a supplier of GEM foils with area of approximately $0.6m^2$. The consortium has developed a double-mask etching technique for production of these large-sized GEM foils. This article describes the production, quality control, and quality assessment (QA/QC) procedures and the mass production status for the GEM foils. Validation procedures indicate that the structure of the Korean foils are in the designed range. Detectors employing the Korean foils satisfy the requirements of the HL-LHC in terms of the effective gain, response uniformity, rate capability, discharge probability, and hardness against discharges. No aging phenomena were observed with a charge collection of $82mC/c{m}^2$. Mass production of KCMS GEM foils is currently in progress.

References in corpus (7)

• A Unified Approach to the Classical Statistical Analysis of Small Signals
• The radiation field in the Gamma Irradiation Facility GIF++ at CERN
• Progress on large area GEMs (VCI 2010)
• Progress on large area GEMs
• Quality Control of Mass-Produced GEM Detectors for the CMS GE1/1 Muon Upgrade
• Research and Development of Commercially Manufactured Large GEM Foils
• Techniques for mass production of large-sized GEM foil by the Korean CMS group for CMS phase-2 upgrade