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Last updated on April 18, 2014 at 1:21 EDT

Large Hadron Collider To Be Offline For Months

September 20, 2008

The world’s largest physics experiment will be delayed for two months after the Large Hadron Collider (LHC) experienced a meltdown due to a defective connection between two magnets, the European Organization for Nuclear Research (Cern) laboratory acknowledged.

The mishap sent temperatures soaring by 100C degrees in a section of the 17-mile underground circuit near the Swiss-French border.

The setback came only one day after the LHC’s beam was restored by the replacement of a faulty transformer that had delayed progress for much of the past week.

The LHC was constructed to smash protons together at extremely high velocity in an attempt to simulate conditions just moments after the Big Bang. Scientists hope the LHC will address some of the most fundamental questions in physics.

Engineers had shutdown part of the experiment during the weekend to probe the failure.  According to a Cern spokesman, the damage to the $6.6bn particle accelerator was worse than initially believed.

A failure, known as a quench, on Friday caused nearly 100 of the LHC’s super-cooled magnets to heat up by as much as 100C.  The fire department was summoned after a ton of liquid helium leaked into the tunnel at Cern, near Geneva.  The quench occurred during the final testing of the last of the LHC’s electrical circuits to be commissioned.

James Gillies , a Cern spokesman, said Saturday that the damaged sector would have to be heated well above absolute zero before repairs could be made.

While admitting the breakdown would be costly, he said the public was never in any danger.    

“A full investigation is still under way but the most likely cause seems to be a faulty electrical connection between two of the magnets which probably melted, leading to a mechanical failure,” he told BBC News.

“We’re investigating and we can’t really say more than that now.

“But we do know that we will have to warm the machine up, make the repair, cool it down, and that’s what brings you to two months of downtime for the LHC.”

The first beams were fired successfully over a week ago around the accelerator’s 16.7-mile underground ring.

The critical next step is to induce a head-on collision between those beams. However, due to the fault, that experiment cannot take place for at least another two months.

At 0927 GMT Friday, the LHC’s online logbook recorded a quench in the accelerator’s sector 3-4, which is located between the Alice and CMS detectors.

The entry stated that helium had been lost to the tunnel, along with vacuum conditions.

The LHC’s superconducting magnets must be supercooled to 1.9 kelvin above absolute zero  before particle beams can be steered around the circuit.

However, the quench caused the temperature of roughly 100 magnets in the machine’s final sector to rise nearly 100C.

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