September 30, 2008

Atom collider facility faces two-month repair

GENEVA

The world’s largest atom smasher — which was launched with great fanfare earlier this month — has been damaged twice and will be out of commission for at least two months, its operators say.

CERN, the European Organization for Nuclear Research, said that a large amount of helium had leaked into the 27-kilometre circular tunnel deep under the Swiss-French border that houses the Large Hadron Collider.

The massive collider began operating September 10, 2008, to the delight of physicists around the world, flinging protons around the circle at nearly the speed of light. But it had to be shut down only 36 hours later due to a failure of an electrical transformer.

That was repaired, but a CERN statement said a second failure took place in the last section of the tunnel to undergo testing at high current, causing the large helium leak.

CERN spokesman James Gillies said the latest incident was several kilometres from the earlier damage. It is considered much more time-consuming to repair than the first malfunction.

“Preliminary investigations indicate that the most likely cause of the (second) problem was a faulty electrical connection between two magnets, which probably melted at high current leading to mechanical failure,” said the statement.

It said the sector will have to be warmed up for repairs to take place, which will require a minimum of two months down time for the collider.

Such faults are common in colliders designed for use at room temperature, and the repair time would be a matter of days, Gillies said. What will slow it down for the LHC is the time it will take to warm up the section and then cool it down again.

The Large Hadron Collider operates at near absolute zero, colder than outer space, for maximum efficiency.

Gillies said it would take “several weeks minimum” to warm up the sector.

“Then we can fix it,” Gillies said. “Then we cool it down again.”

The US$10 billion particle collider, in the design and construction stages for more than two decades, is the world’s largest atom smasher. It fires beams of protons from the nuclei of atoms around the tunnels at nearly the speed of light.

It then causes the protons to collide, revealing how the tiniest particles were first created after the “big bang,” which many theorize was the massive explosion that formed the stars and planets.

Associated Press

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