A physics milestone: Miniature particle accelerator works | Hacker News Reader

A physics milestone: Miniature particle accelerator works

phys.org

87 pointscroes17 comments

The Nature paper: https://www.nature.com/articles/s41586-023-06602-7, and

A corresponding "News and Views" piece: https://www.nature.com/articles/d41586-023-03101-7

Am I the only one imagining this kind of tech eventually turning into something like an electron gun. Sort-of like a real world version of the laser guns in sci-fi? I can imagine basically having a bank of these in a gun where you can shoot a burst and then it would over heat like a plasma gun in warhammer 40k, and you have to wait a bit. Or maybe you can get around this by having some kind of liquid nitrogen cooling system. Of course this could also be used in industry, as a replacement for plasma torches for example. Your only “fuel” would be electricity and you could recirculate the liquid nitrogen into some kind of condenser (compressor?) to be reused. Maybe it could even be used in propulsion in small cube satellites. Obviously right now the tech is in the very early days but these are just some things I can imagine could be possible as the technology matures.

This may be what enables compact high energy gamma ray sources. One example application is scanning cargo containers etc for hidden fissionable material by causing photofission and detecting the neutrons. Very few things emit lots of neutrons when hit with gamma rays below 10 MeV that aren't proliferation related. Gamma rays also don't really activate materials, so scanning something in this way doesn't create radioactive material.

Hobbyist particle accelerator? Is something like that possible?

Would love to see the BOM for this!

Using older technology. Years ago there was a Scientific American Amateur Scientist column that outlined how to make a Van de Graff generator powered particle accelerator. If memory serves that was one of the columns that ended up in C.L. Stong's book of amsci columns.

If memory serves, the van der graff generator at the Boston Museum of Science was literally used as a particle accelerator at MIT for decades (apparently built by the Van de Graaff). I think the generator itself was the accelerator and just needed to go through an evacuated tube to be used.

> The largest air-insulated Van de Graaff generator in the world, built by Dr. Van de Graaff in the 1930s, is now displayed permanently at Boston's Museum of Science. With two conjoined 4.5 m (15 ft) aluminium spheres standing on columns 22 ft (6.7 m) tall, this generator can often obtain 2 MV (2 million volts).

https://en.wikipedia.org/wiki/Van_de_Graaff_generator https://www.atlasobscura.com/places/worlds-largest-airinsula...

Yup, that matches my memory of the AmSci project. Particle source, evacuated tube, generator and target. And shielding, depending on the target.

Obviously, anything you can build in a normal USAian basement is probably not going to be 2MV, but it should be fun anyways.

Depends on your definition I suppose. A CRT screen would qualify according to some definitions.

The vacuum tube alone probably qualifies according to most definitions, it's a beam of charged particles accelerated through the control grid and an accelerator voltage. Honestly not sure what else I'd call that.

Nowadays what would be the closest common thing... hand held XPS exists for sure, but that's not super common (photoelectric effect that uses x-rays coming in). Can we go with an arc welder or plasma cutter if we use a definition that just means "charged particles going through an accelerating voltage in free space"?

I guess an obvious question is can this technique be used to replace eg the LHC?

answered in the article: no. It's mostly useful for medical applications.

No, an LHC beam has energies of over 6 teraelectron volts; this device is only capable of a maximum of 12 kiloelectron volts.

According to the article if they make it 100 times more powerful it would be useful for producing radioisotopes for PET scans, protons for proton therapy, heavy ions for heavy ion therapy, etc. Currently the particle accelerators used in medical facilities are big and expensive so this would make them far more accessible to hospitals world wide.

True, of course, but miniaturization is always lurking in the background of every big physics project. When I was in college, we had a Nobel laureate in physics that won the race to photograph an atom by figuring out how to do it on a tabletop. While everyone else was figuring out how to build bigger and bigger systems, he worked out how to trap a single (I think) cadmium ion with magnets and make it glow.

Yes, they're applying the technique to miniature electronics, I'm wondering what the physical limits are to laser acceleration of particles (protons, say). It seems like you could transfer momentum to any particle traveling slower than might speed - so you could get a relatively high momentum; and you could accelerate neutral particles ...

Why would it not work?

For avoidance of doubt, I'm not imagining a miniature device, just possibly a linear device that is maybe smaller than LHC. They used to use linear arrays prior to development of synchro-cyclotrons, IIRC.

Seems like it would be somewhat akin to a beam of single particle light-sails.

Basically, I was imagining this - https://www.sciencedaily.com/releases/2023/07/230731110723.h... "New method improves proton acceleration with high power laser".

All my best ideas have already been done!

Cannot access the article, but I am not sure these ones can yet access the energies needed for LHC levels of collisions/ resolution.

IIRC, from earlier reports and articles, this will be more useful for biology and chemistry, and perhaps not necessarily for the kind of experimental physics being performed at the LHC.

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