Testing of Track Point Resolution of Gas Electron Multiplier with Pion Beam at CERN SPS

Abstract

The future Compressed Baryonic Matter (CBM) Experiment at FAIR, Germany will measure charmonium and low mass vector mesons by their muonic decay channel with a Muon Chamber (MUCH) detector. Operation of CBM-MUCH at high interaction rate requires a detector with large acceptance, high granularity and high rate capability. First few detector stations at MUCH will use Gas Electron Multiplier (GEM) technology [1, 2] . We have conducted a test experiment with prototype detectors using triple GEM at CERNSPS with 150 GeV/c Pion beam. In CBM experiment, tracks are reconstructed using the hits recorded in a number of Silicon Tracking Stations (STS) placed inside a dipole magnet. Later those tracks are projected onto muon chambers for further reconstruction required for muon detection. The beam undergoes multiple scattering inside the absorbers so tracking may be effected. We report here the estimate of the track-point resolution of the GEM detector using a self-trigger read out ASIC.