Starting Up the Large Hadron Collider

Scientists at CERN are sending proton beams zooming at almost the speed of light around the Large Hadron Collider and colliding them in the center of the LHC's massive particle detectors. Beams began circulating on November 20, and the first collisions at 450 GeV per beam took place on November 23. On November 29 the LHC set a world record for beam energy by accelerating proton beams to 1.18 TeV. Scientists are now increasing the proton beam intensity, or number of particles per beam, and working toward collisions at 1.18 TeV, the maximum energy for 2009. The LHC will shut down December 17 for CERN's two-week holiday break, to be followed by several weeks of work on the accelerator. Collisions will resume at an energy of 3.5 TeV per beam in the first quarter of 2010. These world-record-breaking LHC collisions will launch a new era in mankind's quest to understand the physical universe.

Have questions about the LHC restart and first collisions? You can find answers below:

How can you follow the LHC restart?

News about the LHC restart

How do the LHC and experiments start up? How do collisions happen?

What's happened over the last year?

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