When the world’s most powerful atom smasher attempts a second inaugural switch-on this November, it will be pulling its punches. The Large Hadron Collider, housed underground at CERN on the border between Switzerland and France, will begin its long-awaited first run at half of full energy, and will not reach its full potential until after 2010, CERN has announced.
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The decision, coming after a string of problems with the collider, was a compromise between the need to prevent further damage to the LHC and the need for energies high enough to produce the rare and heavy particles physicists hope to study, says CERN press officer James Gillies.
“We’re still doing the same physics plan we’d envisioned all along,” says Tom LeCompte, physics coordinator for CERN’s ATLAS experiment, which will study collisions of protons. “But it’s happening at a slower pace.”