Compact Muon Solenoid

The Compact Muon Solenoid (CMS) experiment is one of two large general-purpose particle physics detectors being (as of 2007) built on the proton-proton Large Hadron Collider (LHC) at CERN in Switzerland. Approximately 2600 people from 180 scientific institutes form the collaboration building it. It will be located in an underground chamber at Cessy in France, just across the border from Geneva. The completed detector will be cylindrical, 21 metres long and 16 metres diameter and weigh approximately 12,500 tonnes.
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