October 27, 2009

Engineers Inject Particle Beams Into Large Hadron Collider

Engineers have successfully injected beams of particles into two sections of the Large Hadron Collider (LHC), marking the first time particle beams have been inside the LHC since it was shut down in September 2008, BBC News reported.

Scientists working on the giant particle accelerator called it "a milestone" and plan to circulate a beam around the 16 mile-long tunnel in November.

Last year, a magnet problem called a "quench" caused the LHC to leak a ton of liquid helium, forcing it to shut down for repairs shortly after it was switched on.

But engineers have been working to repair the damage and now say that eight sectors of the LHC were cooled to their operating temperature of 1.9 kelvin (-456F) -- colder than deep space.

Beams of protons and lead ions were injected into the LHC ring on October 23 and 25 and successfully guided both clockwise and anti-clockwise through two of the eight sectors.

With such extreme cold, the magnets inside the LHC that align and accelerate the beam become superconducting -- meaning they channel electric current with zero resistance and very little power loss.

The beam test showed that the collider's systems were operating properly, according to Gianluigi Arduini, deputy head of hardware commissioning for the LHC.

He told BBC News it was a work of synchronization.

"The fast magnets must be synchronized to accelerate the beam and transfer it from one accelerator to the next and eventually to the LHC, which must be synchronized to accept it. This whole process happens within 100 picoseconds -- one picosecond is a millionth of a millionth of a second," he explained.

The beams were injected at 450 billion electron volts, only a fraction of the energy that scientists will aim for when they attempt to collide two particle beams.

Experts say two beams of particles will be fired down pipes running through the magnets, where they will be traveling in opposite directions at near the speed of light.

"The aim once the beam is circulating is to accelerate it up to 3.5 trillion electron volts. But that will be in stages. We will first go to one, then 3.5... then from 2011 we're going to try to go to seven," Arduini said.

The proton beams cross paths, smashing into one another at allotted points around the tunnel.

The LHC project is an attempt to see new particles in the debris of these collisions that could reveal insights into the "Big Bang" and how the universe was formed.


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