Test of a GEM detector in the PHENIX experiment at RHIC

GEM detectors can serve as high precision tracking detectors in a variety of high energy and nuclear physics experiments. However, relativistic heavy ion experiments can potentially provide not only very high track multiplicities, but also severe background conditions for operating GEM detectors. To study their use under these conditions, a test was carried out of a three stage GEM detector in the PHENIX experiment at RHIC. The detector was placed in a region close to the collision point inside the PHENIX central spectrometer and operated during full luminosity gold-gold collisions. Results are given on the stability of operation and the sensitivity of the detector to beam related backgrounds using both argon/CO₂ and pure CF₄ gas mixtures.