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Theoretical particle beam weapon

  1. Jul 2, 2012 #1
    This is just for fun so dont take it too seriously...

    So I've read about particle beam weapons and as far as I understand its simply a concentrated beam of particles ie electrons emitted towards an object. I'm pretty sure I'm missing a big piece here when I say it (it just sound too easy) but isnt that what cathode ray tubes are? So couldnt you theoretically just build a bigger tube with a much larger power supply? Or is that the issue, that there isnt a big enough power source to do such a thing, but the idea is sound??

    Also with what I said above in mind, theoretically, if a particle accelerator would simply release the energized particles at something (I dont know, a titanium plate), is that how a particle beam weapon would work? So are particle accelerators particle beam weapons they're just simply too big for any practical use?
    Last edited: Jul 2, 2012
  2. jcsd
  3. Jul 2, 2012 #2
    Well, to do damage, the flux and energy must be both high.
    Consider a fairly cheap (a few million dollar) linear accelerator... its going to be about the size of your living room, weigh a few tons, be fairly finicky, and produce a beam power of a couple milliwatts at ~40MeV in short pulses. Since it is spewing out charged particles, if it even shot them into air, even the air would stop them in a few centimeters.

    Obviously, such a machine isn't anything like ready to be a weapon, even in space. You could shoot it all day at a satellite, and there would be no effect - solar flux is actually much higher. If your aim is good, you might get some gamma damage to electronics.

    So, lets move up to a huge machine, such as Jlab's superconducting linac.
    Now we have a megawatt of power at 6GeV, but it costs tens of billions, and is even more finicky with cryogenic units.
    If you could get the beast built in space, you'd have to power it... and that means nuclear, and then you have to have massive radiators for current nuclear technology. Such a beast would be fragile, and not really viable for a military system.

    http://www.phys.vt.edu/~kimballton/gem-star/workshop/presentations/hutton.pdf goes over the current state of the art in LINACs and should give you an idea of the difficulties.

    One of the advantage of high current density (a very tight beam with high power) is that it would ionize the air and literally push it out of the way, so that the beam could quickly tunnel through air to its target. Thus, attenuation would drop sharply in a fraction of a second, for a very short time (until the air thermalized at the higher temperature). But the installation size, energy needs and lack of robustness preclude military applications.
  4. Jul 3, 2012 #3
    Might be of relevance to the discussion...
    Wiki link
    Last edited: Jul 3, 2012
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