Geneva atom smasher sets March 30 for first try at record high-energy collisions
By Alexander G. Higgins, APTuesday, March 23, 2010
Geneva atom smasher to try record collisions
GENEVA — Operators of the world’s largest atom smasher said Tuesday they will try in a week to collide proton beams at record high energy in a new bid to discover secrets of the universe.
The European Organization for Nuclear Research, or CERN, says beams have been circulating in the Large Hadron Collider at 3.5 trillion electron volts since Friday, 3 1/2 times higher than the previous record set late last year. The operators have kept the beams apart but they will attempt to collide them on March 30.
The higher energy is meant to increase the likelihood that scientists will be able to examine the smallest particles and forces within the atom that could reveal more about the make-up of matter and the universe.
“We’ve still got a lot of work to do before collisions,” said Steve Myers, CERN’s director for accelerators and technology. “Just lining the beams up is a challenge in itself. It’s a bit like firing needles across the Atlantic and getting them to collide half way.”
The collider — housed in a 27-kilometer (17-mile) tunnel under the Swiss-French border at Geneva — has been operating well since November when it was restarted following extensive repairs.
It soon eclipsed the next largest accelerator — the Tevatron at Fermilab near Chicago — pushing its energy to 1.18 trillion electron volts, or TeV. Tevatron operates at 0.98 TeV.
The $10 billion LHC was launched with great fanfare on Sept. 10, 2008, but it was sidetracked nine days later when a badly soldered electrical splice overheated and set off a chain of damage to the massive superconducting magnets and other parts of the collider some 300 feet (100 meters) below the ground.
CERN had to undertake a $40 million program of repairs and improvements before it was ready to retry the machine at the end of November. Then the collider performed almost flawlessly, giving scientists valuable data in the four-week run before Christmas.
CERN specialists have checked out and improved electrical connections and other parts throughout the machine.
The extra energy in Geneva is expected to reveal even more about the unanswered questions of particle physics, such as the existence of antimatter and the search for the Higgs boson, a hypothetical particle that scientist theorize gives mass to other particles and thus to other objects and creatures in the universe.
Scientists hope also to approach on a tiny scale what happened in the first split seconds after the Big Bang, which they theorize was the creation of the universe some 14 billion years ago.
When the collisions start at the new, higher energy, CERN plans to run the collider continuously for 18-24 months, much longer than previously.
This is because the machine operates at near absolute zero degrees, colder than outer space and shutting it off can require months to bring the equipment up to room temperature for any checks, repairs or improvements, CERN said.
The head of CERN, Rolf-Dieter Heuer, said it is likely to take months before any scientific discoveries are made, partly because it takes so long for computers to sort through the massive amount of data produced by the collisions.
Heuer said scientists hope by the end of this year to make discoveries into the mysterious dark matter that scientists believe comprises a quarter of the whole universe; the better understood visible universe makes up only 5 percent of the universe.
Dark matter has been theorized by scientists to account for missing mass and bent light in faraway galaxies. Scientists believe it makes galaxies spin faster.
A separate entity called “dark energy” makes up the remaining 70 percent of the universe, and this is understood to be associated with the vacuum that is evenly distributed in space and time. It is believed to accelerate the expansion of the universe.
After two years of running, the LHC will be shut down for about a year and the specialists will install improvements and make other changes to enable the collider to operate at its design energy of 7 TeV in each direction to produce collisions of 14 TeV.
Physicists have used smaller, room-temperature colliders for decades to study the atom. They once thought protons and neutrons were the smallest components of the atom’s nucleus, but the colliders showed that they are made of quarks and gluons and that there are other forces and particles.