Scientists turn on biggest ‘Big Bang Machine’

Alan Boyle Science editor • Profile • E-mail

After 14 years of preparation, a new scientific wonder of the world opened for business Wednesday with the official startup of Europe's Large Hadron Collider.

The $10 billion particle accelerator is the biggest, most expensive science machine on earth, designed to probe mysteries ranging from dark matter and missing antimatter to the existence of extra, unseen dimensions in space.

Scientists, journalists and dignitaries watched from the control room at Europe's CERN particle-physics center on the French-Swiss border, near Geneva, as beams of protons were sent all the way around the collider's 17-mile (27-kilometer) underground ring of supercooled pipes for the first time.

"Today is a great day for CERN," the organization's director general, Robert Aymar, told the crowd in the control room as the startup process began.

Controllers checked the alignment of the beam as barriers were removed at each stage of the route. Applause and shouts greeted every report of progress along the 330-foot-deep (100-meter-deep) tunnel — climaxing when the beam made its first full clockwise circuit, less than an hour after it was turned on.

"It’s a fantastic moment," Lyn Evans, the project leader for the Large Hadron Collider, said afterward. "We can now look forward to a new era of understanding about the origins and evolution of the universe.”

As champagne flowed in the control room, former CERN chief Luciano Maiani noted that the money spent on the project over 14 years was a mere fraction of the $40 billion that China spent for this summer's Olympic Games in Beijing. "These are the Olympics of science," CERN spokeswoman Paola Catapano replied during a Webcast interview.

Hours later, the LHC's counterclockwise proton beam made its first-ever circuit. The next steps in the process will be to fine-tune the beams and bring them together for their first collisions. It will take weeks for the collider to go through its commissioning process, and the LHC isn't expected to reach full power until next year.

‘First Beam,’ first celebration
Even though the first scientific results are months away, CERN used Wednesday's "First Beam" events as a high-profile occasion for celebration. For the more than 10,000 scientists, engineers and other workers involved in the project, the Large Hadron Collider represents a revolutionary new research opportunity as well as an unprecedented engineering achievement.

Video   The biggest physics experiment Sept. 10: ITN's Lawrence McGinty reports on the startup of the world's largest particle collider. Nightly News

"The combination of the size, scale, complexity and technology — well, the comparison I always use is the pyramids," Peter Limon, a U.S. physicist from Fermilab who played a part in building the device, said during a pre-startup walkthrough. "This is what we do today comparable to the pyramids of 4,000 years ago."

The LHC is designed to do things the pyramid's builders never imagined.

Once the machine is in full operation, two streams of invisible protons will be whipped up in opposite directions around an underground racetrack to 99.999999 percent of the speed of light. When the two waves of protons slam into each other, scientists expect particles to melt into bits of energy up to 100,000 times hotter than the sun's core — a state that should replicate what the entire universe was like just an instant after it came into being.

How can the Large Hadron Collider possibly perform such feats? That's where the wonder begins.

Going down ...
No one was allowed in the underground tunnel for Wednesday's maiden run, but a visit during the final phases of the LHC's construction provided an inside look at the wonder at work.

During the seven-year construction phase, components of the collider and its detectors had to be lowered down piecemeal from CERN's assembly halls, then put together in underground caverns as big as cathedrals.

Although the scale of the project is impressive, these cathedrals are no gleaming shrines to science: Our trip felt more like going into the bowels of a well-worn power plant or subway system. That's because most of the facility was actually carved out in the 1980s for an earlier particle-smasher called the Large Electron Positron collider, or LEP. CERN has spent the past seven years remodeling the space for the Large Hadron Collider.

Steven Nahn, a physicist at the Massachusetts Institute of Technology, conducted research at CERN during the LEP era. "They stole our tunnel, that's the way I see it," Nahn joked as Limon showed us around.

For years, Nahn, Limon and thousands of other researchers have pitched in on the design and assembly of the LHC's instruments, forsaking quiet laboratories for the din of the construction site — as well as the occasional industrial mishap.

The LHC tunnel: Misbehaving magnets
Limon is a veteran of Fermilab's Tevatron, which had been the world's most powerful collider but is being dethroned by the LHC. At full power, the proton beams at the LHC will run into each other with the force of two 400-ton bullet trains going 100 mph. That amounts to 14 trillion electron volts, or about seven times the Tevatron's maximum power.

To bend those subatomic bullet trains into a circular path requires a chain of more than 1,800 superconducting magnets that have been chilled so close to absolute zero that they're colder than the average temperature of outer space (1.9 Kelvin, or 456.3 degrees below zero Fahrenheit).

Some of those magnets have to be collimated to focus the beams precisely at the ring's four collision points, like a telescope focusing light onto its mirrors. Drawing on its experience from Tevatron, Fermilab was put in charge of providing many of those magnets. But back in March 2007, a design flaw led to a violent breakdown during a cooldown test. The supports that held the magnet in place came loose with a loud bang and a cloud of dust.

"Everybody ducked about two seconds after it happened," Limon recalled.

The LHC's scheduled startup had to be delayed 10 months to install and test a fix for the faulty magnets. Even with the fix, there's no guarantee that the magnetic field will always hold. A runaway proton beam could blast right through its helium-cooled pipeline and kill anyone who got in its way. That's why the tunnel is sealed off for each run. If anything goes wrong, a computer-controlled system will shut down the collider and send the errant beam down a blind alley within milliseconds.

However, if everything goes right, each pulse of protons will whip around the ring 11,000 times a second, traveling the equivalent of a trip to Neptune and back before they slam into the protons going the other way at four points around the ring. Four main detectors will watch what happens next.

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