Image:
MARTIAL TREZZINI  /  AP
After a year's delay, scientists at Europe’s CERN physics research center have sent beams of protons circulating all the way through the Large Hadron Collider.
By
updated 11/20/2009 7:15:02 PM ET 2009-11-21T00:15:02

Scientists switched on the world's largest atom smasher Friday night for the first time since the $10 billion machine suffered a spectacular failure more than a year ago.

It took a year of repairs before beams of protons circulated late Friday in the Large Hadron Collider for the first time since it was heavily damaged by a simple electrical fault.

Circulation of the beams was a significant leap forward. 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.

Progress on restarting the machine, on the border between Switzerland and France, went faster than expected Friday evening and the first beam circulated in a clockwise direction around the machine about 10 p.m., said James Gillies, spokesman for the European Organization for Nuclear Research.

"Some of the scientists had gone home and had to be called back in," Gillies told The Associated Press.

The exact time of the start of the Large Hadron Collider was difficult to predict because it was based on how long it took to perform steps along the way, and in the end it happened about nine hours earlier than expected, Gillies said.

This is an important milestone on the road toward scientific discoveries at the LHC, which are expected in 2010, he said.

About two hours later the scientists circulated another beam in the opposite direction, which was the initial goal in getting the machine going again and moving it toward collisions of protons, CERN said. The LHC also will be used later for colliding lead ions — basically the nucleus of the element that is about 160 times as heavy as a single proton. That should reveal still more scientific secrets.

"It's great to see beam circulating in the LHC again," said CERN Director General Rolf Heuer. "We've still got some way to go before physics can begin, but with this milestone we're well on the way."

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 massive superconducting magnets and other parts of the collider, in a 27-kilometer (17-mile) circular tunnel under the Swiss-French border.

CERN has $40 million on repairs and improvements on the machine to avoid a repetition.

"The LHC is a far better understood machine than it was a year ago," said Steve Myers, CERN's director for accelerators. "We've learned from our experience and engineered the technology that allows us to move on. That's how progress is made."

The LHC is expected soon to be running with more energy the world's current most powerful accelerator, the Tevatron at Fermilab near Chicago. It is supposed to keep ramping up to seven times the energy of Fermilab in coming years.

Slideshow: Building the biggest collider (on this page) This will allow the collisions between protons on the machine to give insights into dark matter and what gives mass to other particles, and to show what matter was in the microseconds of rapid cooling after the Big Bang that many scientists theorize marked the creation of the universe billions of years ago.

The two parallel tubes the size of fire hoses send billions of protons whizzing around the collider in opposite directions at nearly the speed of light. In rooms the size of cathedrals 300 feet (100 meters) below the ground the magnets force them into huge detectors to record what happens.

The beams traveled Friday night at a relatively low energy level, but Gillies said the LHC was expected soon to start accelerating them soon so that the collisions they make will be more powerful — and revealing — creating as yet unseen insights into nature.

The LHC operates at nearly absolute zero temperature, colder than outer space, which allows the superconducting magnets to guide the protons most efficiently.

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. And scientists still have other questions about antimatter, dark matter and supersymmetry they want to answer with CERN's new collider.

The Superconducting Super Collider being built in Texas would have been bigger than the LHC, but in 1993 the U.S. Congress canceled it after costs soared and questions were raised about its scientific value

"The next important milestone will be low-energy collisions, expected in about a week from now," said Gillies.

These will give the experiments their first collision data, enabling them to calibrate their equipment for the scientific work ahead, eagerly awaited by particle physicists from countries around the world, he said.

Until now all the data they have recorded has comes from cosmic rays from outer space.

Gillies said the LHC should be ramped up to 3.5 trillion electron volts some time next year, which will be 3 1/2 times as powerful as Fermilab. The two laboratories are friendly rivals, working on equipment and sharing scientists.

But each would be delighted to make the discovery of the elusive Higgs boson, the particle or field that theoretical gives mass to other particles. That is widely expected to deserve the Nobel Prize for physics.

More than 8,000 physicists from other labs around the world also have work planned for the LHC. The organization is run by its 20 European member nations, with support from other countries, including observers Japan, India, Russia and the U.S. that have made big contributions to the LHC.

CERN has received support from around the world in getting the LHC up and running again, the organization said.

"It's been a Herculean effort to get to where we are today," said Myers. "I'd like to thank all those who have taken part, from CERN and from our partner institutions around the world."

© 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Photos: How the biggest collider was built

loading photos...
  1. Heart of the machine

    A worker stands inside the ATLAS detector, surrounded by its eight toroidal magnets, just before the installation of the machine's calorimeter. ATLAS, the largest particle detector at Europe's Large Hadron Collider, sits inside an underground cavern as big as a cathedral. (Maximilien Brice / CERN) Back to slideshow navigation
  2. Mission control

    Members of the ATLAS detector team monitor operations at their control room on the campus of Europe's CERN particle-physics research center. A cutaway view of the particle detector can be seen on the computer screen at far right. (Claudia Marcelloni / CERN) Back to slideshow navigation
  3. Down the hole

    The last of 1,746 superconducting magnets is lowered into the Large Hadron Collider's beamline tunnel via a specially constructed pit in April 2007, as seen in this fish-eye view. Dipole magnets like this one produce a magnetic field that is 100,000 times stronger than Earth's, to bend beams of subatomic particles around the circular accelerator. (Claudia Marcelloni / CERN) Back to slideshow navigation
  4. Making the connection

    A welder works on the interconnection between two of the Large Hadron Collider's superconducting magnet systems in the collider tunnel. (Maximilien Brice  / CERN) Back to slideshow navigation
  5. Wheel of fortune

    One of the wheel-shaped slices of the ATLAS muon detector is lowered into a cavern for assembly into a giant device designed to look for evidence of exotic subatomic particles such as the Higgs boson. The Higgs particle is thought to play a key role in producing the property of mass in the universe. (Claudia Marcelloni & J. Pequenao / CERN) Back to slideshow navigation
  6. The theorist and the experiment

    World-famous theoretical physicist Stephen Hawking takes a look at the Large Hadron Collider's underground beamline during a visit in September 2006. (CERN) Back to slideshow navigation
  7. Pulling the trigger

    Each experiment at the Large Hadron Collider requires a "trigger," a combination of hardware and software that decides which collisions are significant enough to pass along for further analysis. This is a fish-eye view inside the trigger chambers for the ALICE detector's muon spectrometer. (Aurelien Muller / CERN) Back to slideshow navigation
  8. Inside the big bang

    A technician from the ALICE installation team works on gas pipes for the detector. ALICE is designed to study lead-ion collisions so intense that they re-create the conditions that existed just after the big bang. (A. Saba & Mona Schweizer / CERN) Back to slideshow navigation
  9. Cycles within cycles

    Technicians often use bicycles to get around the Large Hadron Collider's 17-mile-round tunnel. (Maximilien Brice / CERN) Back to slideshow navigation
  10. Dwarfed by science

    The LHCb detector is designed to study why matter dominates over antimatter in the universe. The worker peeking out from the concrete barriers at left is dwarfed by the detector's lip-shaped magnet assembly at right. (CERN) Back to slideshow navigation
  11. The PC farm

    CERN's Computer Center stores the quadrillions of bytes of data generated by experiments at the Large Hadron Collider and distribute the information to thousands of researchers around the world, using a network known as the LHC Computing Grid. (Maximilien Brice / CERN) Back to slideshow navigation
  1. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  2. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  3. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  4. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

Discuss:

Discussion comments

,