Studies of etching effects on triple-GEM detectors operated with CF/sub 4/-based gas mixtures

摘要

We present the results of a global irradiation test of full size triple-GEM detectors operated with a CF/sub 4/-based gas mixture. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV /spl gamma/ from a /sup 60/Co source. After the irradiation test the detectors' performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in the GEM detector during the strong irradiation.