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Helium Ion Particle Accelerator

  1. Sep 28, 2014 #1
    Okay you're going to have to forgive me but i'm new to all of this and i'm still getting a hang of this website(as well as having little or no education/experience in much of any physics beyond highschool),but I was wondering if it would be possible to make a particle accelerator that used helium not xenon and permanent magnets such as neodymium magnets?

    From the basic research that i've done it takes 54 ev to fully ionize a Helium-3 particle,whereas it would take 32 for a Xenon particle,any thoughts/ideas/advice?
     
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  3. Sep 28, 2014 #2

    mfb

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    You can accelerate every type of ion. But not with permanent magnets, as they do not change the energy of particles.
    Fully ionizing Xenon takes much more energy than ionizing helium - more than 1 keV for the last electron alone, and neutral Xenon has 54 of them (although most of them are significantly easier to remove).
     
  4. Sep 29, 2014 #3
    My only thought behind the permanent magnets was it wouldn't take anymore electricity than is necessary to ionize the helium, but my idea behind the permanent magnets was to focus the ion stream down after its running.

    Do you have to accelerate the ions using the magnets?
     
  5. Sep 29, 2014 #4

    mfb

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    Where and how do you want to use permanent magnets?

    As quadrupoles to focus ion beams: yeah sure, you can do that, if those weak magnets are sufficient for your accelerator. Same thing applies to dipoles for bending the beam.
     
  6. Sep 29, 2014 #5

    marcusl

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    Acceleration is done electrically, either by electrostatic field (van de Graaf, e.g.) or the field inside of an RF cavity (cyclotron, linear accelerator, etc.)
     
  7. Sep 29, 2014 #6
    As quadrupoles to focus the ion beam,as far as the electrostatic field is concerned could you use a copper helix with a pulsed charge to accelerate the ions? Or maybe use the magnets as quadrupoles but at a 45 degree angle or something like that to not only focus but also push the ion stream forward?
     
  8. Sep 29, 2014 #7

    marcusl

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    You asked for advice in your first post. Please don't take this the wrong way, I'm trying to be helpful--it is apparent from your posts that you lack the understanding and mastery of electromagnetism required to tackle a project of this complexity and sophistication. I suggest starting with something smaller and simpler.
     
  9. Sep 29, 2014 #8
    I most certainly due lack understanding and mastery,the only reason I started out focusing on this is because I found it the most interesting project at that particular moment.
     
  10. Sep 29, 2014 #9
    Understanding is the main reason I came here.
     
  11. Sep 29, 2014 #10

    marcusl

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    Oh. I assumed, from the wording in your post, that you were trying to build an accelerator.
     
  12. Sep 29, 2014 #11

    e.bar.goum

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    There are manufacturers that will sell permanent magnet focusing elements (dipoles, at least, I haven't ever seen a quadrupole system from permanent magnets) for particle accelerators - they're marketed as greener, as they don't require power or water cooling.The ones I have seen for sale also have an electromagnet component, presumably to tune the magnet slightly.

    The downside, of course, is that they are suitable only if you only ever want to make one beam, of one energy. So they have a somewhat limited market.

    On accelerating helium - you can do that, of course, but not all particle accelerators accelerate positive ions. Van de Graaff type tandem accelerators inject negative ions, and as you can't form a negative ion of helium, you can't make that kind of beam.

    But for accelerators that inject positive ions, you don't actually have to fully strip the ion. One electron will do, but the acceleration is less (and in that way, you can modulate the beam energy you end up with).
     
  13. Sep 30, 2014 #12

    mfb

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    Maybe, but it would be extremely ineffective.

    Static magnetic fields cannot increase the speed of particles, no matter how their orientation is.
     
  14. Sep 30, 2014 #13

    ZapperZ

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    There are a couple of issues here that the OP have misunderstood.

    1. As has been stated, magnetic field CANNOT impart any acceleration to a charged particle. So this scheme is faulty.

    2. Secondly, the reason why we do not use a permanent magnet for focusing, positioning, bending, etc. is because the current, or bunches of charge that are moving are often of different amount. Different particle currents require different magnetic strengths to accomplish the same thing. With a permanent magnet, you are STUCK with one field strength and have no way of adjusting the field to accomplish whatever it is that you want to accomplish. One does not design something with this kind of unnecessary restriction.

    This post also has more to do with classical E&M than particle physics.

    Zz.
     
  15. Sep 30, 2014 #14

    Vanadium 50

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    Zz, is of course, correct.

    I know of one major ring that uses permanent magnets - the Fermilab recycler. This has 358 permanent magnets. But,
    1. It's a fixed energy storage ring - not an accelerator
    2. It also has 129 powered magnets for orbit control.
    While I appreciate the OP's enthusiasm, it is difficult to discuss improvements to accelerator designs before understanding the basics of their operation - such as that one needs electric fields to change the energy of particles. Magnetic fields can only change direction.
     
  16. Sep 30, 2014 #15
    I apologize if my original wording was misleading,and thank you all for the advice I will endeavour to educate myself further on the subject and try to start out a little less ambitiously,I do however have one more question regarding this subject,what is the best method for accelerating ions?
     
  17. Sep 30, 2014 #16

    ZapperZ

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    Electric field.

    However, this is like saying the Pacific ocean is only a body of water. There is A LOT of complicated details on the nature and geometry of such an electric field. In a typical accelerator, this is accomplished by a time-varying RF field in an accelerating structure.

    I would suggest that you start off with just learning the basic of E&M.

    Zz.
     
  18. Sep 30, 2014 #17
    Okay thanks.
     
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