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Magnetic field produced in a particle accelerator?

  1. Oct 3, 2013 #1
    I have no idea if this is the right place for this topic.
    Recently, I have been reading about particle accelerator operation and theory. I had never realized exactly how the particles were accelerated. Turns out the particles are are bunched together in clumps by an ac wave and accelerated.

    Question: since the particles are in clumps rather than spread out in the tube, is the magnetic field they produce uniform or non-uniform? In other words, could the magnetic field produced by these particles in motion induce a current in a nearby coil?

    Thanks in advance!
  2. jcsd
  3. Oct 3, 2013 #2
    Theoretically they could yes practically although I doubt that any noticeable effect would take place due to the amount and density of those accelerated protons at a accelerator tube.

    but in overall yes the principle works like that , current is induced when something which has charge moves near or through a conductor , a coil whatever.
    Since charged particles like protons have electric field around them when they are moving perpendicular to a coil like in the particle accelerator or any other coil/ coils they can induce a current which induces a back EMF which slows down the particles and so on .It doesn't matter if they are in clumps or not , well for the field to be uniform it matters but for their fields to induce a current in a coil it doesn't matter , you will ahve a current in a coil if you would move charged particles near it both ways in clumps or not.
    By the way if you have protons only they cannot even be in clumps because they are all positive and repel each other kinda strongly.

    How much this effect takes place in facilities like CERN and their particle guiding magnets along the tubes they travel , I'm sure we have people like Zapper and other here who will tell you that.
  4. Oct 3, 2013 #3
    Ok, thanks for the response.

    is it not true that you need a non-uniform magnetic field to induce a current in a coil?
  5. Oct 3, 2013 #4


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    The buncher and acceleration frequency on the machines we operation (high-energy linear accelerator based ion implanter) is 13.56mhz so it's very easy to induce an RF current from the 'clumps' in a coil placed near the beamline. The average DC component could be up to 1ma @ 1meV at the wafers.

    For the energy levels (1 to 3 meV) we require AC acceleration is not always needed because you can use a tandem DC accelerator instead.

    tandem DC accelerator
  6. Oct 3, 2013 #5
    thanks for the info. Thats very interesting. I'll look into tandem dc accelerators
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