The Performance of INFN Made Gas Electron Multiplier (GEM) Detectors During the Neutron Magnetic Form Factor (Gⁿ_M) Experiment

The GnM experiment in Hall A, which uses the 12 GeV electron accelerator at Jefferson Lab and is the first part of the Super BigBite Spectrometer (SBS) program, measures the neutron magnetic form factor for Q2 up to 13.5 (GeV/c)2. The measurement of GnM will be extracted using the ratio of neutron-coincident to proton-coincident quasi-elastic electrons scattered off deuterium. The extraction of GnM by this ‘ratio’ method promises improved precision in the previously measured kinematic regime with projected systematic errors of the measured ratio of the cross sections varying by 2% to 5%. The experiment is performed using the BigBite Spectrometer which detects the scattered electrons, and the Super BigBite Spectrometer which detects the scattered nucleons using a large aperture dipole magnet and Hadron Calorimeter. A main component of the BigBite Spectrometer are Gas Electron Multiplier (GEM) tracking detectors. Some of which were manufactured by Istuito Nazionale di Fisica Nucleare (INFN) and were designed to handle a charged particle flux of 160 kHz/cm2. The scope of this talk will be an overview of the physics goals for the GnM experiment and a brief description of the INFN GEM detector performance during the experiment.