Nanotech accelerator-on-a-chip

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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Schneibster
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Location: Monterey, CA, USA

Nanotech accelerator-on-a-chip

Postby Schneibster » Sat Sep 28, 2013 8:39 pm

http://news.stanford.edu/news/2013/sept ... 92713.html

I think the applications to polywell and similar ideas are fairly obvious.

Also, I've heard a lot of moaning by a lot of particle physicists about how big accelerators were going to have to be in the future; I suspect this might have some pretty strong effects on that, too. If you could make one of these things to accelerate protons at a GeV/m we might be looking at an unexpected extra generation or two of solid-state accelerators. I suspect this might be possible using much finer grooves and an X-ray free electron laser. The questions of whether it works will be answered by the ability of the material to withstand the X-rays and the accelerating particles, and the ability to localize the accelerating particles within the grooves without them quantum jumping around and introducing too many complications for good coherence.

The operating principle is that as electrons pass through the rainbow-looking part in the middle of the image, tiny grooves catch the laser photons and cause them to interact as a field with the charged electrons, accelerating them. In most existing accelerators microwaves are used, which are more diffuse than laser photons by orders of magnitude and therefore require beam paths miles long instead of feet like these new accelerators take up.

The rainbow is of course the expected effect of a very fine diffraction grating of parallel lines, which is precisely what this device uses for its active principle.

Also note the lack of supercooled magnets.
We need a directorate of science, and we need it to be voted on only by scientists. You don't get to vote on reality. Get over it. Elected officials that deny the findings of the Science Directorate are subject to immediate impeachment for incompetence.

Enginerd
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Joined: Sun Feb 07, 2010 5:29 am

Re: Nanotech accelerator-on-a-chip

Postby Enginerd » Sun Sep 29, 2013 7:50 pm

Schneibster wrote:I think the applications to polywell and similar ideas are fairly obvious.


Presumably these would make some very nice electron guns to fill
up the Polywell wiffle ball, replacing the electrons lost to the grid.

<not a accelerator expert>
What would it take to make this thing shoot i.e. ions rather than electrons?

If this is cheap, small, highly reliable, sufficiently powerful, and able to maintain a
very high rate, and if this could shoot a beam of ions, one could set up shop using
a spallation target to make an excellent small neutron source.

This might make an accelerator driven subcritical reactors actually feasible. Presumably,
given the same sort of accelerator, someone could begin manufacturing rare heavy
metals like copper, silver, and gold, etc. Presumably however bad guys could similarly
use this to manufacture plutonium the same way Glen Seaborg did. I suppose it depends
on how many neutrons this could make. There is a reason they built Hanford, since the
best they could produce at the time using their cyclotron was micrograms, and they needed
bazliilons more neutrons to get to pounds.
"Reality is that which, when you stop believing in it, doesn't go away."
--Philip K. Dick

Schneibster
Posts: 1805
Joined: Mon Jul 09, 2007 5:21 am
Location: Monterey, CA, USA

Re: Nanotech accelerator-on-a-chip

Postby Schneibster » Sun Sep 29, 2013 10:15 pm

Enginerd wrote:
Schneibster wrote:I think the applications to polywell and similar ideas are fairly obvious.


Presumably these would make some very nice electron guns to fill
up the Polywell wiffle ball, replacing the electrons lost to the grid.

<not a accelerator expert>
What would it take to make this thing shoot i.e. ions rather than electrons?
I suspect a relation between the laser wavelength, the charged particle's DeBroglie wavelength, and the widths of the slots in the grid. Maybe only one or two of those elements, but I'd be surprised if it weren't all three.

Finding out could be fun and I'll look into it.

Enginerd wrote:If this is cheap, small, highly reliable, sufficiently powerful, and able to maintain a
very high rate, and if this could shoot a beam of ions, one could set up shop using
a spallation target to make an excellent small neutron source.
The sticking point would be if the interatomic forces in the glass were sufficient to retain structural integrity in the face of relatively massive particles like ions; or, at least for a while, maybe you gotta replace them, oh, every week, or every year or whatnot.

Another point to keep in mind is that if you want more mass than electrons provide mesons may be more tractable, since they're less massive; baryons like neutrons and protons may be too massive for interatomic forces to stand up to. But a pion beam might work. Another direction to go might be muons or tauons.

Enginerd wrote:This might make an accelerator driven subcritical reactors actually feasible.
Mmmm, I'd expect that to be ungainly for hand-carried or small personal transportation applications; but think about this: nano-reactors. :D

Enginerd wrote:Presumably, given the same sort of accelerator, someone could begin manufacturing rare heavy
metals like copper, silver, and gold, etc. Presumably however bad guys could similarly
use this to manufacture plutonium the same way Glen Seaborg did. I suppose it depends
on how many neutrons this could make. There is a reason they built Hanford, since the
best they could produce at the time using their cyclotron was micrograms, and they needed
bazliilons more neutrons to get to pounds.
I think the problem with producing plutonium this way would be the same problem with producing precious metals. Doesn't sound practical.

Seaborg was just pushing an experimental technique as far as it would go to see what he'd get. You got them to pay for it; might as well squeeze the last least drop of information out of it.

My guess is the nearest-term use would be ion implant.
We need a directorate of science, and we need it to be voted on only by scientists. You don't get to vote on reality. Get over it. Elected officials that deny the findings of the Science Directorate are subject to immediate impeachment for incompetence.


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