Large Hadron Collider Gets Set for Weekend Restart

The Large Hadron Collider is gearing up to resume shooting beams of protons through its vast underground ring of magnets sometime between Saturday and Monday, after a two-year shutdown for upgrades and a weeklong delay due to a short circuit. "We are confident of being able to restart the machine over the weekend, as all of the tests performed so far have been successful," Frederick Bordry, director for accelerators and technology at Europe's CERN particle physics center, said in a statement issued Thursday.

The LHC and its thousands of researchers made history in 2012 when they announced the discovery of the Higgs boson — a subatomic particle that represented the last missing puzzle piece for the Standard Model, one of physics' most successful theories. During its first run, the particle collider at the French-Swiss border smashed proton beams together at energies of up to 8 trillion electron volts, or 8 TeV. For the second run, the dial will be turned up to 13 TeV. At those energy levels, physicists hope to detect exotic particles that could explain the properties of mysterious dark matter — and they also may find evidence of microscopic black holes and weird, rolled-up spatial dimensions.

At first, proton beams will be circulated at energies of 450 billion electron volts, or 450 GeV. CERN said particle collisions could ramp up to the 13 TeV level as early as June.

World's Most Complex Machine Gets Ready for More Atom-Smashing 2:23



— Alan Boyle