Now, super-powerful tabletop particle accelerator

Physicists have built a super-powerful tabletop particle accelerator that can generate energies and speeds previously reached only by major facilities, shrinking the size from the length of two football fields to just one inch.

“We have accelerated about half a billion electrons to 2 giga-electronvolts over a distance of about one inch,” said Mike Downer, professor of physics in the College of Natural Sciences at The University of Texas at Austin.

“Until now that degree of energy and focus has required a conventional accelerator that stretches more than the length of two football fields. It’s a downsizing of a factor of approximately 10,000,” said Downer.

The results mark a major milestone in the advance toward the day when multi-gigaelectronvolt (GeV) laser plasma accelerators are standard equipment in research laboratories around the world, researchers said.

Downer said he expects 10 GeV accelerators of a few inches in length to be developed within the next few years, and he believes 20 GeV accelerators of similar size could be developed within a decade.

Downer said that the electrons from the current 2 GeV accelerator can be converted into “hard” X-rays as bright as those from large-scale facilities.

He believes that with further refinement they could even drive an X-ray free electron laser, the brightest X-ray source currently available to science.

A tabletop X-ray laser would be transformative for chemists and biologists, who could use the bright X-rays to study the molecular basis of matter and life with atomic precision, and femtosecond time resolution, without travelling to a large national facility.

“The X-rays we’ll be able to produce are of femtosecond duration, which is the time scale on which molecules vibrate and the fastest chemical reactions take place.

“They will have the energy and brightness to enable us to see, for example, the atomic structure of single protein molecules in a living sample,” said Downer.

To generate the energetic electrons capable of producing these X-rays, Downer and his colleagues employed an acceleration method known as laser-plasma acceleration.

Downer said that now that he and his team have demonstrated the workability of the 2 GeV accelerator, it should be only a matter of time until 10 GeV accelerators are built. That threshold is significant because 10 GeV devices would be able to do the X-ray analyses that biologists and chemists want.

The study was published in Nature Communications.