The Large Hadron Collider (LHC) is being built in a circular tunnel 27 km in circumference. The tunnel is buried around 50 to 175 m. underground. It straddles the Swiss and French borders on the outskirts of Geneva.
LHC - the aim of the exercise:- To smash protons moving at 99.999999% of the speed of light into each other and so recreate conditions a fraction of a second after the big bang. The LHC experiments try and work out what happened.
It is designed to collide two counter rotating beams of protons or heavy ions. Proton-proton collisions are foreseen at an energy of 7 TeV per beam with a planned start-up in 2007.
High energy beams move around the LHC ring inside a continuous vacuum guided by magnets.
The magnets are superconducting and are cooled by a huge cryogenics system. The cables conduct current without resistance in their superconducting state.
The beams will be stored at high energy for hours. During this time collisions take place inside the four main LHC experiments.
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