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Down and Out in France and Switzerland

Nine days after the Large Hadron Collider (LHC) turned on its proton beam for the first time, the LHC needed to be turned off. Over the weekend the agency running the Collider announced that an accident damaged the magnets that guide the beam, putting the LHC out of commission for at least two months as scientists work to repair the equipment.

According to CERN, the organization that manages the LHC, a coolant line ruptured midday on Friday September 19th while scientists conducted a test to ensure the components were working properly. The accident damaged a magnet and resulted in coolant leaking into the final section of the 17-mile long tunnel that houses the LHC. An early investigation by CERN revealed that faulty wiring between two giant magnets melted while testing the magnets performance at high voltage, causing the mechanical failure of the coolant line.

The super conducting magnets of the LHC conduct the proton beam around the track and into the collisions that the scientists will study. To function properly, the magnets need to be kept near absolute zero, the theoretical lowest possible temperature where the random vibration of atoms comes to a halt. To keep the magnets that cold, lines of liquid helium 1.9 degrees C warmer than absolute zero run through the magnetic tubes. The extreme cold needed for the experiment also contributes to the length of the repair time, as it takes weeks to heat the elements enough to be replaced, and will take another couple of weeks to cool them down again to such a low temperature.

However according to James Gillies, a spokesperson for CERN, the accident won’t delay all of the work at the LHC. “”There won’t be people sitting around twiddling their thumbs during this time,” said Gillies, adding that what work will be conducted during the down time has yet to be decided.

UPDATE: Apparently the damage to the LHC was more extensive than previously reported by CERN. The facility will now be shut down for a year, not 2 months, according to reports released September 23,2008.