The Resistive Plate Chamber detectors at the Large Hadron Collider experiments

by Roberto Guida (Univ. + INFN)

Friday 2 Oct 2009, 11:00 → 12:00 Europe/Zurich

40-S2-D01 (CERN)

Abstract: The Resistive Plate Chamber (RPC) detectors are extensively employed at the Large Hadron Collider (LHC) experiments. The relatively low production cost, combined with a high time resolution (~ ns) and a suitable spatial resolution (~ cm), make RPC appealing for large muon trigger systems (up to more than 5000 m2). RPC’s are suitably operated in avalanche mode using a three component non-flammable gas mixture: 94.7 % of R134a (C2H2F4), 5 % of iC4H10 and 0.3 % of SF6. Water vapour should be added to the mixture in order to maintain a relative humidity of about 45 % and avoid any changes of the bakelite resistivity. Numerous tests have been performed in the past 10 years in order to ensure the detector functionalities over a long period and in conditions similar to the ones foreseen during the LHC running. More recently, increasing attention has been addressed to the study of the gas quality and to the possible formation of corrosive compounds during the detector operation with high particle rate. In fact, for economical reasons, the chamber gas for the ATLAS and CMS RPC’s is operated in 90-95% closed loop circulation with in-line purification. The removal of harmful gas impurities produced in the chamber is an essential element to guarantee good and long-lived chamber operation. Detector Seminar webpage Organizer: Ferdinand HAHN / PH-DT

Slides Roberto_RPCDetectorSeminar_v2.pdf Roberto_RPCDetectorSeminar_v2.ppt