부산대학교 도서관

At the CERN LHC experiments, several gaseous detector technologies are operated in gas recirculation mode to lower operational costs and gas emissions. In the next years, Micro Pattern Gaseous Detector (MPGD) technologies will be largely implemented in the LHC experiments, with dedicated gas systems, and they will experience a significantly increased background radiation rate, especially in the HL-LHC phase. It is therefore fundamental to study MPGD operated with LHC gas systems, especially under gas recirculation, to be able to guarantee their safe long-term operation. In this context, the performance of Gas Electron Multiplier (GEM) detectors operated in gas recirculating systems have been studied at the CERN Gamma Irradiation Facility (GIF ++ ), which provides an intense gamma irradiation along with a Muon beam from the SPS accelerator. Triple-GEM detectors performance has been studied in relation to operation stability during long-term high rate irradiation, as well as in terms of Muon detection efficiency with different gamma background rates. Both tests were realized with various gas mixtures and gas system conditions. A complete overview of the results obtained at the GIF ++ is presented, showing the successful operation of Triple-GEM detectors during long-term high-rate irradiation and good Muon detection efficiency in HL-like background radiation.