Evaluation of GEM tracking quality at MUSE*

The MUon Scattering Experiment (MUSE) at Paul-Scherrer Institute (PSI) will measure the proton charge radius by scattering of muons and electrons from the proton. The experiment uses a telescope of three Gas Electron Multiplier (GEM) detectors to track the beam paticle that is later scattered. This presensation will show the transformation of the track location at each GEM element compared with the local coordinates of the hits on each element. Three GEM elements will be used to make a track and the quality of the track will be assessed using the hits on the fourth GEM element.