Large Hadron Collider Back Online Following Two-Year-Plus Refit

Following a shutdown of over two years for upgrades, the Large Hadron Collider — no doubt one of the largest pieces of hot hardware in the world — was brought back online yesterday at CERN in Geneva, Switzerland. The LHC, which made good on its promise of delivering the Higgs boson in 2012, is now at last poised to begin making scientific history once again.


“Congratulations,” CERN Director General Rolf-Dieter Heuer said to thousands of staff members from the control room of the Large Hadron Collider. “Now the hard work starts.”

The news of the LHC's firing back to life was especially gratifying, as early last week it looked as though the resumption of proton-smashing by the LHC would be delayed another few months when a short circuit was uncovered in one of the Collider's dipole circuits mere days before particle finding work was set to resume. Engineers, though, quickly located the problem - a small piece of metal debris - and removed it, and the LHC restart was right back on track.

A complex instrument such as the LHC takes some time to come back online, and for the past few weeks it has been prepared to once again receive beams of protons shooting around the 17-mile Collider at nearly the speed of light. Then, at 10:41 GMT+1 on Easter Sunday the first beam of protons made a circuit around the $4.4bn LHC, with a second beam completing a lap in the other direction at 12:27 without incident.


“The beam went smoothly through the whole machine. It’s fantastic to see it going so well after two years and such a major overhaul of the LHC,” said Heuer.

The Large Hadron Collider restart was accomplished with relatively weak beams of protons, however within weeks the energy of the beams will be juked up to the target level of 13 TeV (teraelectronvolts) — almost twice the level possible before the refit — with the resumption of actual particle collisions set for June.