Big Bang atom smasher starts speeding proton beams

Wednesday, November 25, 2009 at 2:42 AM Posted by Beijing News


GENEVA – The world's largest atom smasher used its accelerator Tuesday to speed up proton beams for the first time as scientists moved ahead in efforts to learn more about the universe.

The $10 billion Large Hadron Collider showed it could raise the energy of the proton beams whizzing around the massive machine by an initial 20 percent.

"It was just a preliminary test," said James Gillies, spokesman for the European Organization for Nuclear Research, also known as CERN. "It's all going very well."

Tuesday's step indicated further good news for the collider since months of repairs following its spectacular collapse last year. The latest phase began Friday night when the first proton beams circulated each way around the 17-mile 27-kilometer tunnel under the Swiss-French border.

The operators then got the beams to run simultaneously in opposite directions through fire-hose-sized pipes 11,000 times a second around the ring, zooming by at nearly the speed of light through temperatures colder than outer space.

Ultimately, the collider aims to create conditions like they were 1 trillionth to 2 trillionths of a second after the Big Bang — which scientists think marked the creation of the universe billions of years ago. Physicists also hope the collider will help them see and understand other suspected phenomena, such as dark matter, antimatter and supersymmetry.

On Monday, the collider's four massive detectors saw the first collisions between protons as the beams crossed each other at set points in rooms the size of cathedrals 100 meters 300 feet underground.

Physicists say the beam is of superb quality, with the protons tightly packed into hairlike lines and guided by 1,600 superconducting magnets — some of them 15 meters 50 feet long — around the ring.

While the initial collisions were a side effect, intentional hits could begin within the next 10 days, mainly to check how the machine is working, Gillies said. The initial collisions are needed to calibrate the machine.

Gillies said Tuesday the energy of the proton beam was increased to 540 from 450 billion electron volts, still a long way from the power that will be needed for new discoveries in the makeup of the universe and matter. Those discoveries might start happening in the first half of next year.

"They set in process the procedure to ramp the machine up to the 1.2 TeV trillion electron volts that we want to get to this year," Gillies said.

That level would make the Geneva machine the world's most powerful collider, overtaking the Tevatron at Fermilab near Chicago, which operates at 1 trillion electron volts.

The Geneva accelerator automatically stopped when it rose to about 540 billion electron volts, about 90 billion electron volts higher than it had been operating so far, Gillies said.

After that, the proton beam was halted Tuesday for maintenance checks on the machine, he said.

The collider's first science test will take place in January or early February, when scientists plan to start deliberately crashing protons into each other to see what they can discover about the makeup of the universe and its tiniest particles.

Physicists said the discoveries could begin after the collider reaches 3.5 TeV in each direction.

The collider was started with great fanfare Sept. 10, 2008, only to be heavily damaged by an electrical fault nine days later. It took 14 months to repair and add protection systems to the machine before it was restarted. The overall price of repairs and improvements is expected to cost $40 million, according to CERN.

That is because the Higgs boson is believed to be hard to see and needs powerful energy to be revealed.

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