The Large Hadron Collider
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What is the LHC?
- The Large Hadron Collider (LHC) is the world's largest particle accelerator. Built at CERN, on the French-Swiss border, it lies 175m underground in a ring 27km (17 miles) in circumference!
- It works by accelerating two beams of particles called protons until they're travelling at just under the speed of light. It then smashes these beams together so scientists can try understand what makes protons and all other matter behave the way it does.
- It was built by CERN, the European Organization for Nuclear Research to test leading theories of high energy physics. Despite working on the sub-atomic level it has huge implications for all of science and physics, including astronomy.
- The LHC is designed to search for the Higgs Boson, a particle predicted by science but never seen. It is thought that this particle is what gives all other particles their mass.
- One of the stranger things about the LHC is that to see smaller and smaller particles we need to build larger and larger equipment. This is why the LHC is the biggest scientific experiment in history, with over 10,000 scientists and engineers, from more than 100 countries, working at CERN.
The interior of the LHC. For a sense of scale, note the man standing at the bottom of the picture.
What does the Large Hadron Collider have to do with astronomy?
A lot, it turns out. The main force in astronomy is gravity. It's what keeps us on Earth and the Earth orbiting around the Sun.
Without gravity stars and planets wouldn't be able to form and life could not exist.
All particles that have mass are affected by gravity but we still don't understand what mass is or why some particles like those
in atoms have mass and why some particles like photons don't. One reason the LHC was built was to find out what it is that gives
matter its mass.
Most scientists think that mass comes from a small particle called the Higgs Boson. Although it's never been seen scientists have been able to predict a lot of its qualities based on what we already know about the universe. Because of this they hope to find the Higgs Boson using the LHC. Whether we find it or not will tell us a lot about the universe and just how good our theories of it are!
Large Hadron Collider switched on
On Wednesday, September 10th 2008, the LHC in CERN was switched on. Although initial tests passed everybody's expectations,
a fault on the 19th September caused an explosion which shut down the LHC for over a year.
On Friday, 20th November 2009, the LHC was restarted.
On the evening of Tuesday, 8th December 2009, the LHC recorded beam collisions with a world record beating energy of 2.36TeV!
This is roughly the same energy as a 400-tonne train travelling at 150km per hour!
The record was beaten when scientists first collided particles on Tuesday March 30 2010. The collisions happened at an energy of 7Tev,
half of the LHC's full power!
The LHC will continue at half power until 2012 when it will shut down for a year to re-check the parts which had been damaged in the explosion before cranking it up to full power with beams of particles colliding at 14TeV! This is about 70,000 times more energetic than the processes in an atomic bomb!
