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Pressure gauge at the cryogenics plant at CERN (the European particle physics laboratory) in Switzerland. The plant is responsible for cryogenically cooling the Large Hadron Collider (LHC), a 27-kilometre-long high-energy particle accelerator. The LHC uses rings of superconducting magnets to accelerate two counter-rotating beams of protons to an energy of 7 teraelectronvolts (TeV). It then forces these beams to collide head-on near two main detectors, known as the CMS (Compact Muon Solenoid) and ATLAS (A Toroidal LHC Apparatus), which detect the sub-atomic particles resulting from the collision. The plant cools the magnets with liquid helium, to keep the operating temperature at just above absolute zero. The LHC is scheduled to start operating in summer 2008. (KEYSTONE/SCIENCE PHOTO LIBRARY/ADAM HART-DAVIS/SCIENCE PHOTO LIBRARY)