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Electron beam/atmosphere interaction

  1. Jul 14, 2008 #1

    This is something that's puzzled me for a while, but I haven't been able to find any conclusive answers anywhere. What I'm wondering is, how far would an electron beam (such as that found in a TV) travel in the atmosphere before it lost its kinetic energy or bonded with the air molecules?

    I've heard about particle beam weapons being researched for anti-missile applications and such, so that makes me think it could potentially go quite a ways...any answers or even suggestions as to where I could look would be greatly appreciated!
  2. jcsd
  3. Jul 14, 2008 #2


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    The electron mean free path in air is of the order of [itex]10^{-6}[/itex] m for an energy of the order of 10's of eV. It doesn't make a very good weapon, I would think.

  4. Jul 17, 2008 #3
    Thanks for the quick reply, that's exactly what I was looking for!

    Makes me wonder why they're researching them for military applications (for example, Medusa) though.
  5. Jul 17, 2008 #4

    Doc Al

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    MEDUSA uses a beam of microwave pulses, not electrons. To make any kind of a serious electron beam weapon, you'd have to accelerate the electrons to very high energy.

    As Zz stated, low energy electrons (10's of eV) won't get very far in the atmosphere. I used to do electron scattering experiments at those energies--those experiments had to be done in a high vacuum chamber.
  6. Jul 17, 2008 #5
    Ah ok, thanks for clearing that up for me.
  7. Jul 17, 2008 #6


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    I think that most of the research into electron beams as anti-missile weapons were assuming the interception of ICBM's outside the atmosphere by an orbiting weapons platform. Electron beams make fairly decent weapons in a vacuum, especially against a target with sensitive electronics on board.
  8. Dec 27, 2011 #7
    Can this technology be used to complete an electrical circiut between conductors at any distance? Develop to detonate IED?
  9. Dec 27, 2011 #8


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    It would not complete a circuit unless it melts something and causes a short. Whether this is possible using microwaves I am unsure. (which is what I'm assuming your referring to, as an electron beam would be stopped by a few mm's of ground) If the electronics are shielded, which isn't hard, then I don't think so.
    Although if it could be used as an IED detonator or minesweeper it would be pretty cool.
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