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Cyclotron Magnet

  1. May 20, 2003 #1
    I'm trying to build a small cyclotron and am thus searching for a magnet. I've been looking for a neodythium disc magnet that I could have cut in half to act as the two 'D' magnets in the cyclotron. The size of the magnet needs be somewhere around 12" in diameter but I can't seem to find anyplace that sells them around this size. If anyone knows where I could find some magnets or is willing to sell some of their own that would be great.
  2. jcsd
  3. May 20, 2003 #2
    A couple of advices.

    1.Don't try to cut neodym alloy - you won't be able to do that at home (it is very and very hard alloy). Ferrite is a little better, but too brittle. So, just get 2 magnets instead.

    2. If you can't find two large magnets (equipment surplus web places can be a good place to start a search - Ti ion vacuum pumps have quite big slabs of ferrite magnets), then buy many small magnets and make a big one.
    Last edited by a moderator: May 20, 2003
  4. May 20, 2003 #3
    why dont you start with a high-voltage linear accelerator and see how that goes first? you just need a very strong tube, a pump, and a voltage difference from either transformer or van de graff generator.
  5. May 21, 2003 #4


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    The dees will need to be electromagnets, not permanent magnets.

    - Warren
  6. May 21, 2003 #5
    That's true, they will. And you might want to consult relavant physics textbook for equations and etc.
  7. May 21, 2003 #6
    Thanks for all of the responses. First off, I've already built a linear accelerater using my own voltage multiplier I made, a pump, etc. I also know all the equations for figuring out the frequency I need to alternate the current, what the velocity of the particle given a certain strength of a magnetic field is and the length of path taken, etc.

    When I first started thinking about this, I too thought I needed elctromagnets but then my high school physics teacher told me I needed permanent magnets. Thus, I was hoping to find a strong neomydium magnet disc that I could have someone professionally cut into two parts so I could have my two dee magnets. I guess now I need to search out for electromagnets, so if anyone knows where some are, that would be great!
  8. May 22, 2003 #7
    That is for synchrotron. For cyclotron an orbit just gets bigger and bigger with velocity.
  9. May 22, 2003 #8
  10. May 22, 2003 #9


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    Er, uh...

    You'll still need a strong permanent magnet to curve the paths of the particles (ions, electrons, etc.) in a cyclotron.

    However, the poster was asking about the DEES -- which are, of course, not permanent magnets. They are, in fact, not magnets at all. The dees are two halves of a hollow metal disc, to which an oscillating electric potential is applied.

    - Warren
  11. May 22, 2003 #10
    If only I would have read this a few hours before. I just tossed a huge electromagnet.

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