Construction and Performance of full scale GEM prototypes for future upgrades of the CMS forward Muon system

Abstract

In the prospect of an upgrade of the CMS Experiment, an international collaboration is performing feasibility studies on employing large-area triple-GEM detectors for the high-η region (1.6-2.4) of the CMS Endcap, which is currently not instrumented. Given their good spatial resolution, high rate capability, and radiation hardness, these micro-pattern gas detectors are an appealing option for simultaneously enhancing muon tracking and triggering capabilities in this region. A detailed review of the development and characterization of small and full-size (1m x 0.5m) prototypes will be presented. These full-size GEM foils are produced using a novel single-mask etching technique developed at CERN. In addition, we discuss the performance of a full-size trapezoidal triple-GEM detector in a strong magnetic field during a dedicated beam test campaign to address CMS requirements on the detectors.