Characterization of GEM Detectors in the BM@N Experiment

In the BM@N experiment (for Baryonic Matter at the Nuclotron), nucleus–nucleus collisions under extreme conditions will be investigated for elements up to gold. The high collision rate and a large charged-particle multiplicity per collision dictate that the employed detectors should show high spatial and time resolutions and stable operation at occupancies up to 10 6 /cm 2 . Multilayer GEM (Gas Electron Multiplier) devices that satisfy these criteria have therefore been chosen as constituent elements of the main tracking system. In this paper, we describe the design of the GEM detector employed in the BM@N experiment and report the results of its characterization.