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Texas Physicists Create Tabletop Particle Accelerator
An anonymous reader sends this quote from a University of Texas news release:
"Physicists at The University of Texas at Austin have built a tabletop particle accelerator that can generate energies and speeds previously reached only by major facilities that are hundreds of meters long and cost hundreds of millions of dollars to build (abstract). 'We have accelerated about half a billion electrons to 2 gigaelectronvolts over a distance of about 1 inch,' said Mike Downer, professor of physics in the College of Natural Sciences. '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.' ... 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 traveling to a large national facility."
now to make it back pack sized!
Area needed for experimental appratus: One 6' folding table from Office Depot
Equipment needed: One petawatt-class laser, occupying a large portion of the physics building
Egon Spengler would only say "Don't cross the streams".
I don't believe this story at all.
Now, if the summary had said something about some high school kid doing it for the science fair for under $200, that I can believe.
If you want news from today, you have to come back tomorrow.
We already have had fairly cheap "tabletop" (or small car-sized) accelerators for a long, long time. Accelerating electrons to 2GeV is not terribly complicated.
However, accelerating a LARGE number of electrons is complicated. Accelerating a large number of ions is even more so. That's why LHC is necessary - you can't hope get enough luminosity with small tools, even if you can reach the same energies.
Well, a CRT accelerates electrons up to around 30 000 eV. This gets them up to 2 000 000 000 eV in roughly the same size, so I'd say it's a little more complicated than that.
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The press release makes some very grand-sounding claims about replacing synchrotrons and free-electron lasers. I'm not an expert in the accelerator field but I've used these systems, and I have some idea of what the actual output needs to be in order to be useful for biologists. Specifically, it's not just the electron energies that matter, but the photon flux per unit of area. The figures for modern synchrotrons are on the order of 10^11 - 10^13 with a spot size of 100 microns or less - the very best will focus down to just a few microns. From what I can understand of the paper, they're talking about several orders of magnitude fewer photons over much larger areas. (If someone who understands this stuff better can confirm whether or not I'm reading it correctly, I'd be grateful.) The only hard free-electron laser in the US, the LCLS at Stanford, is orders of magnitude brighter than synchrotrons, and compressed into pulses on the order of tens of femtoseconds long.
It would be great if someone could build a high-intensity hard X-ray source at every big research university. But it's not the first time such claims have been made; there is (or was) a company called Lyncean that tried to build a tabletop synchrotron in the previous decade, and made similar predictions about its utility for biology. Their technology worked perfectly well from a theoretical standpoint - but it was several orders of magnitude too weak to be competitive with existing synchrotron beamlines, and too expensive to be competitive with existing laboratory X-ray sources.
(Of course this is pretty much standard stuff from university PR departments, which would always like you to believe that they're on the brink of curing caner or revolutionizing some widely used method. The actual Nature Communications article is much more sober.)
Only what you see here, pal.
If you Google "2 BeV accelerator," the first relevant hit is a scanned typewritten document [slashdot.org] from CERN.
Maybe because "BeV" is really antiquated and not too long after accelerators reached that energy level, GeV became standardized.
As far as use, there are some hard limits on current accelerator technology that requires them to be scaled up to make large gains in energy. The hope is that work like this will continue to go to higher energy levels and eventually allow for surpassing the highest energy accelerators without having to dig a large hole. Although that will be potentially quite difficult, as it is not as simple as just make a longer version of the new tech to increase the energy, so to some degree, the total energy they get is a lot more relevant than the energy per distance.