Laser-plasma 'tabletop' particle accelerator sets record

BERKELEY, Calif., Dec. 9 (UPI) -- Researchers have accelerated particles to unheard-of speeds using a record-setting compact accelerator. The device was developed by researchers at the U.S. Department of Energy's Lawrence Berkeley National Lab and is small enough to fit on a kitchen table.

It can produce acceleration energy of roughly 4.25 giga-electron volts -- a record for laser-plasma accelerators and more than 1,000 times as powerful as a larger standard particle accelerator.

The "tabletop" accelerator uses the world's most powerful laser to fire electrons down a plasma tube just 3.5 inches in length. By comparison, CERN's Large Hadron Collider features a tube that circles and reconnects, completing 17-mile loop.

Whereas larger traditional accelerators, like CERN's, use the manipulation of electromagnetic fields to propel electrons, the new tabletop device is powered by BELLA (Berkeley Lab Laser Accelerator). Not only is BELLA the most powerful laser in the world, it's also one of the most precise -- an essential quality for accelerating electrons over such a short distance.

"This result requires exquisite control over the laser and the plasma," Dr. Wim Leemans, the director of the lab's Applied Physics Division, explained in a press release. The work of Leemans and his colleagues was published in the Physical Review Letters.

As scientists explain it, BELLA clears a channel through the plasma tube. The laser's energy pushes waves of trapped free electrons through the channel, accelerating them to high energies.

"It's similar to the way that a surfer gains speed when skimming down the face of a wave," Berkeley Lab officials wrote.

"It is an extraordinary achievement for Dr. Leemans and his team to produce this record-breaking result in their first operational campaign with BELLA," said Dr. James Symons, the lab's associate director for physical sciences.

Leemans and his fellow researchers say that if they can find a way to more precisely control the size of the plasma channel, they should be able to reach even higher levels of of acceleration energy.