Quick Restart of Atom Smasher Stuns Scientists

ALEXANDER G. HIGGINS,
Associated Press Writer

GENEVA—Scientists moved Saturday to prepare the world's largest atom smasher for exploring the depths of matter after successfully restarting the $10 billion machine following more than a year of repairs.

The nuclear physicists working on the Large Hadron Collider were surprised that they could so quickly get beams of protons whizzing near the speed of light during the restart late Friday, said James Gillies, spokesman for the European Organization for Nuclear Research.

The machine was heavily damaged by a simple electrical fault in September last year.

Some scientists had gone home early Friday and had to be called back as the project jumped ahead, Gillies said.

At a meeting early Saturday "they basically had to tear up the first few pages of their PowerPoint presentation which had outlined the procedures that they were planning to follow," he said. "That was all wrapped up by midnight. They are going through the paces really very fast."

The European Organization for Nuclear Research has taken the restart of the collider step by step to avoid further setbacks as it moves toward new scientific experiments — probably starting in January — regarding the makeup of matter and the universe.

CERN, as it is known, had hoped by 7 a.m. (0600 GMT) Saturday to get the beams to travel the 27-kilometer (17-mile) circular tunnel under the Swiss-French border, but things went so well Friday evening that they had achieved the operation seven hours earlier.

Praise from scientists around the world was quick. "First beam through the Atlas!" whooped an Internet message from Adam Yurkewicz, an American scientist working on the massive Atlas detector on the machine.

"I congratulate the scientists and engineers that have worked to get the LHC back up and running," said Dennis Kovar of the U.S. Department of Energy, which participates in the project.

He called the machine "unprecedented in size, in complexity, and in the scope of the international collaboration that has built it over the last 15 years."

Later Saturday the organizers decided to test all the protection equipment while there still is a very low intensity proton beam circulating in the collider at 11,000 times a second. The tests will take 10 days, Gillies said.

The current beam has relatively few protons to avoid damage to the LHC should control of them be lost.

Gillies said CERN decided against immediately testing the LHC's ability to speed up the beams to higher energy or to start with low-energy collisions that would help scientist calibrate their detection equipment.

In the meantime CERN is using about 2,000 superconducting magnets — some of them 15 meters (50 feet) long — to improve control of the beams of billions of protons so they will remain tightly bunched and stay clear of sensitive equipment.

Gillies said the scientists are being very conservative.

"They're leaving a lot of time so that the guys who are operating the machine are under no pressure whatsoever to tick off the boxes and move forward," he said.

Officials said Friday evening's progress was an important step on the road toward scientific discoveries at the LHC, which are expected in 2010.

"We've still got some way to go before physics can begin, but with this milestone we're well on the way," CERN Director General Rolf Heuer said.

With great fanfare, CERN circulated its first beams Sept. 10, 2008. But the machine was sidetracked nine days later when a badly soldered electrical splice overheated and set off a chain of damage to the magnets and other parts of the collider.