Wednesday, September 10, 2008
Scientists beaming after test of big atom smasher
GENEVA (AP) — A small blip on a computer screen sent champagne corks popping among physicists in Switzerland. Near Chicago, researchers at a "pajama party" who watched via satellite let out an early morning cheer.
The blip was literally of cosmic proportions, representing a new tool to probe the birth of the universe.
The world's largest atom smasher passed its first test Wednesday as scientists said their powerful tool is almost ready to reveal how the tiniest particles were first created after the "big bang," which many theorize was the massive explosion that formed the stars, planets and everything.
Rivals and friends turned out in the wee hours at Fermilab in Batavia, Ill., in pajamas to watch the event by a special satellite connection. Joining in from around the world were other physicists — many of whom may one day work on the new Large Hadron Collider.
Tension mounted in the five control rooms at CERN, the European Organization for Nuclear Research, as scientists huddled around computer screens. After a few trial runs, they fired a beam of protons clockwise around the 17-mile tunnel of the collider deep under the rolling fields along the Swiss-French border. Then they succeeded in sending another beam in the opposite, counterclockwise direction.
The physicists celebrated with champagne when the white dots flashed on the blue screens of the control room, showing a successful crossing of the finish line on the $10 billion machine under planning since 1984.
"The first technical challenge has been met," said a jubilant Robert Aymar, director-general of CERN. "What you have just seen is the result of 20 years of effort. It all went like clockwork. Now it's for the physicists to show us what they can do.
"They are ready to go for discoveries," Aymar said. "Man has always shown he wants to know where he comes from and where he will go, where the universe comes from and where it will go. So here we're looking at essential questions for mankind."
The beams will gradually be filled with more protons and fired at near the speed of light in opposite directions around the tunnel, making 11,000 circuits a second. They will travel down the middle of two tubes about the width of fire hoses, speeding through a vacuum that is colder than outer space. At four points in the tunnel, the scientist will use giant magnets to cross the beams and cause protons to collide. The collider's two largest detectors — essentially huge digital cameras weighing thousands of tons — are capable of taking millions of snapshots a second.
It is likely to be several weeks before the first significant collisions.
The CERN experiments could reveal more about "dark matter," antimatter and possibly hidden dimensions of space and time. It could also find evidence of a hypothetical particle — the Higgs boson — which is sometimes called the "God particle" because it is believed to give mass to all other particles, and thus to matter that makes up the universe.
Smaller colliders have been used for decades to study the makeup of the atom. Scientists once thought protons and neutrons were the smallest components of an atom's nucleus, but experiments have shown that protons and neutrons are made of quarks and gluons and that there are other forces and particles.
The LHC provides much greater power than earlier colliders.
Its start came over the objections of some who feared the collision of protons could eventually imperil the Earth by creating micro black holes — subatomic versions of collapsed stars whose gravity is so strong they can suck in planets and other stars.
"It's nonsense," said James Gillies, chief spokesman for CERN, which also received support for the project by leading scientists such as Britain's Stephen Hawking.
Gillies said the only risk would be if a beam at full power were to go out of control, and that would only damage the accelerator itself and burrow into the rock around the tunnel. No one would be endangered because the tunnel is evacuated when beams are being fired.
No such problem occurred Wednesday, although the accelerator is still probably a year away from full power.
The project organized by the 20 European member nations of CERN has attracted researchers from 80 nations. Some 1,200 are from the United States, an observer country that contributed $531 million. Japan, Canada, Russia and India — also observers — are other major contributors.
Some scientists have been waiting for 20 years to use the LHC.
The complexity of manufacturing it required groundbreaking advances in the use of supercooled, superconducting equipment. The 2001 start and 2005 completion dates were pushed back by two years each, and the cost of the construction was 25 percent higher than originally budgeted in 1996, said Luciano Maiani, who was CERN director-general at the time.
Maiani and the other three former directors-general attended Wednesday's experiment.