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The '''Large Hadron Collider''' (LHC)  is a [[particle accelerator]], with a circumference of 27km,  located at the [[CERN]] facility which straddles the border of France and Switzerland. Built over 15 years at a cost of $9 billion, it is the largest and most ambitious piece of machinery ever conceived and built by man.

The '''Large Hadron Collider''' (LHC)  is a [[particle accelerator]], with a circumference of 27 km,  located at the [[CERN]] facility which straddles the border of France and Switzerland. Built over 15 years at a cost of $9 billion, it is the largest and most ambitious piece of machinery ever conceived and built by man.

==Design==

==Design==

The collider was built to accelerate protons to energies of seven trillion electron volts and smash them together in search of particles and forces that reigned earlier than the first trillionth of a second of time, but the machine could run as low as four trillion electron volts for its first year. Upgrades are scheduled already.  

The collider was built to accelerate protons to energies of seven trillion electron volts and smash them together in search of particles and forces that reigned earlier than the first trillionth of a second of time, but the machine could run as low as four trillion electron volts for its first year. Upgrades are scheduled already.  

The LHC was powered up on 10 September 2008, with the first beams being circulated through the collider. It reached full power in mid-November 2008, which is when scientists were supposed to begin smashing [[particle]]s into each other. This was hampered however as the LHC suffered a mechanical breakdown just as it was switched on and it was not active again until early 2010.  Numerous major problems have emerged and it may take years before the machine is fully operational.<ref> See [http://www.nytimes.com/2009/08/04/science/earth/04collide.html?ref=world "Giant Particle Collider Fizzles," Dennis Overbye ''New York Times'' Aug. 3, 2009]</ref>

The LHC was powered up on 10 September 2008, with the first beams being circulated through the collider. It reached full power in mid-November 2008, which is when scientists were supposed to begin smashing [[particle]]s into each other. This was hampered however as the LHC suffered a mechanical breakdown just as it was switched on and it was not active again until early 2010.  Numerous major problems have emerged and it may take years before the machine is fully operational.<ref>See [http://www.nytimes.com/2009/08/04/science/earth/04collide.html?ref=world "Giant Particle Collider Fizzles," Dennis Overbye ''New York Times'' Aug. 3, 2009]</ref>

==Challenges==

==Challenges==

<references/>

<references/>

==External Links==

==External links==

[http://lhc.web.cern.ch/lhc LHC] Homepage at CERN.

* [http://lhc.web.cern.ch/lhc LHC] Homepage at CERN.

[[Category:Physics]]

[[Category:Physics]]