3 ms·

The exciting part of this is the gradient. The addition of 1keV in 30um is huge! For reference, in a typical electron microscope, accelerating fields might rea

The exciting part of this is the gradient. The addition of 1keV in 30um is huge! For reference, in a typical electron microscope, accelerating fields might reach a 1 MeV/m gradient. In these cases, it's usually an anode (-200kV) and cathode (0V) closely separated. High vacuum is required, it's large, power supplies are enormous, etc. Scaling the results of this paper, especially after a working prototype, will be more interesting to the general population. But the key discoveries are already here. Scaling becomes an engineering concern.

ianai 7y ago
So what’s stopping us from being able to convert energy to mass with a particle accelerator? Shouldn’t it be possible to get a particle of equivalent mass-energy to the energy concentrated by an accelerator? So like amp up an electron to 106 MeV and get a muon-on-demand?
- scentoni 7y ago
  Well, muons are made by getting electrons or other particles up to high speeds and then crashing them into stationary targets or counterrotating beams. But you have to create muon-antimuon pairs, so that requires at least 212 MeV in theory and much more in practice because of energy lost to heat, etc. https://www.fnal.gov/pub/today/SpecialROW032808MERIT.html https://www.fnal.gov/pub/today/SpecialROW032808MERIT.html
  - ianai 7y ago
    Per google, you have to have a collision because of the law of conservation of momentum otherwise won’t allow for pair production. It’s an open question how we get a universe of matter out of seemingly only producing mass energy in matter/anti-matter symmetry. Sounds like a sure Nobel prize for that one, too.
jandrese 7y ago
Is there any reason they couldn't chain a whole bunch together to kick up to higher energy levels? Say you need 50um per segment for the support framework and whatnot, you could pack 200 of them in a cm long instrument and kick up the power by 200keV?
- cosmic_quanta 7y ago
  Oh yes, that's what I would anticipate. The design shown in this paper is specific to an initial electron energy of 83keV. That means that chaining identical parts wouldn't work, but you could have an array of similar parts with slightly different properties at each "stage".

ianai 7y ago

So what’s stopping us from being able to convert energy to mass with a particle accelerator? Shouldn’t it be possible to get a particle of equivalent mass-energy to the energy concentrated by an accelerator? So like amp up an electron to 106 MeV and get a muon-on-demand?

scentoni 7y ago
Well, muons are made by getting electrons or other particles up to high speeds and then crashing them into stationary targets or counterrotating beams. But you have to create muon-antimuon pairs, so that requires at least 212 MeV in theory and much more in practice because of energy lost to heat, etc. https://www.fnal.gov/pub/today/SpecialROW032808MERIT.html https://www.fnal.gov/pub/today/SpecialROW032808MERIT.html
- ianai 7y ago
  Per google, you have to have a collision because of the law of conservation of momentum otherwise won’t allow for pair production. It’s an open question how we get a universe of matter out of seemingly only producing mass energy in matter/anti-matter symmetry. Sounds like a sure Nobel prize for that one, too.

jandrese 7y ago

Is there any reason they couldn't chain a whole bunch together to kick up to higher energy levels? Say you need 50um per segment for the support framework and whatnot, you could pack 200 of them in a cm long instrument and kick up the power by 200keV?

cosmic_quanta 7y ago
Oh yes, that's what I would anticipate. The design shown in this paper is specific to an initial electron energy of 83keV. That means that chaining identical parts wouldn't work, but you could have an array of similar parts with slightly different properties at each "stage".