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Particle Accelerator

  1. Sep 25, 2003 #1
    I was wondering how to build a particle accelerator at home. If it is possible, please tell me how. Thank You
    -ATCG
     
  2. jcsd
  3. Sep 25, 2003 #2

    jcsd

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    No it isn't, partricle accelrators are huge devices which are miles long/have a radius of miles and use extremely powerful magnets in order to get the particles up to the required speed.
     
  4. Sep 25, 2003 #3

    Nereid

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    Actually, you probably have several in your house right now ... your computer monitor (unless it's a liquid crystal flat screen), your TV set (again, unless it's a flat panel liquid crystal one), your fluorescent light tubes, ...

    The standard cathode ray tube is an electron accelerator (and electrons are particles).

    What sort of particles do you wish to accelerate? To what sorts of energies?
     
  5. Sep 25, 2003 #4

    chroot

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    You can build a small cyclotron in your home with nothing more than a modest vacuum pump, some sort of cylindrical vacuum flask, a couple of carefully manufacturered D-shaped electrodes, and some simple electronics. The whole thing could be no larger than a few feet in diameter.

    The easiest thing to do is to evacuate the flask and use the particles (mostly nitrogen atoms) in the rarefied gas left over as projectiles.

    The energies won't be high, but you can certainly do some simple experiments with your crude nitrogen beam.

    - Warren
     
  6. Sep 25, 2003 #5
    I would be trying to create anti-matter
     
  7. Sep 25, 2003 #6

    jcsd

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    What kind of anti-matter, you can create anti-neutrinos from beta-decay (In the UK at least you usually need a license to handle any radioactive materials), creating any other kind of antimatter is going to be more difficult esp. anti-baryons.
     
  8. Sep 25, 2003 #7

    Nereid

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    You could always build a cloud chamber, and watch the cosmic rays go through it. Every so often you'll see some anti-matter ...
     
  9. Sep 26, 2003 #8

    russ_watters

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    Your warp engines running low on gas?

    I read once that anti-matter is th most expensive "substance" in the world.
     
  10. Sep 26, 2003 #9

    Nereid

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    Russ said:
    More likely to be super-heavy elements (Lr, Rf, ... through to Uuo (element 118))
     
  11. Sep 26, 2003 #10

    chroot

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    Given the energies needed to perform this, I can pretty convincingly say you're not going to get it to happen on your tabletop. And even if you did, how would you use it? You need some pretty sophisticated machinery to separate and store antimatter.

    You may be interested to know that some kinds of targets, such as lead, are commonly used to "convert" photons into particle-antiparticle pairs.

    - Warren
     
  12. Sep 26, 2003 #11

    pmb

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    That's incorrect. People have actually built particle accelerators at home. From - www.fnal.gov/pub/inquiring/questions/homemade_particle_accl.html
    I believe he's talking about this person
    http://www-personal.umich.edu/~mrniell/cyc2.html [Broken]


    A good place to start would be to look at how the first cyclotron was made. See - "The Production of High Speed Light Ions Without the Use of High Voltages," Ernest O. Lawrence and M. Stanley Livingston, University of California. February 1932 --
    http://prola.aps.org/abstract/PR/v40/i1/p19_1

    For an image of a table-top accelerator see
    http://www.aip.org/history/lawrence/larger-image-page/first-11.htm

    See also -
    http://www.aip.org/history/lawrence/first_text.htm
    http://www.aps.org/apsnews/0603/060316.html
    http://www.lbl.gov/Science-Articles/Archive/early-years.html
    http://www.lbl.gov/nsd/user88/chchist1.html [Broken] (???)

    The first cyclotron could actually be held in your hand
    http://www.fnal.gov/pub/inquiring/timeline/15.html
    http://www.llnl.gov/llnl/history/eolawrence.html [Broken]
    http://science.howstuffworks.com/atom-smasher2.htm

    ATCG - If you build one please keep me informed. I'd love to follow your progress.

    Pete
     
    Last edited by a moderator: May 1, 2017
  13. Sep 26, 2003 #12

    chroot

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    THAT'S CYCLOTRON BOY!

    I remember seeing his (award-winning) science fair project at the 1994 International Science and Engineering Fair in Hamilton, Ontario, Canada!!! My clique of students took quickly to giving him the endearing name of 'cyclotron boy,' and making up stories about his parents forcing him to stay in the basement, subsisting on bread and water, working his fingers to the bone to make his cyclotron.

    Talk about a small world!

    My only complaint with his entire experiment was that he obfuscated it as much as possible. He didn't just buy a vacuum pump -- no -- he took one apart and stuck all its components on a big piece of plywood, lengthening hoses as necessary, to make it look more imposing. He really did a first-rate job, though -- he was studying mass resonance, I believe, and took some reasonably useful data with his crude apparatus. He certainly did deserve the 1st grand award in physics.

    - Warren
     
    Last edited: Sep 26, 2003
  14. Sep 26, 2003 #13
    Could someone link me to a web site the has detailed schematics on how to build a cyclotron or Particle accelerator?

    Thanks
    -ATCG
     
  15. Sep 27, 2003 #14

    pmb

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    Did you look at this page??
    http://www-personal.umich.edu/~mrniell/cyc2.html [Broken]

    Try e-mailing the author/owner of that site and ask him of the blueprints and schematics (one's online are not very legible).

    His e-mail address is - mrniell@umich.edu

    Pete
     
    Last edited by a moderator: May 1, 2017
  16. Nov 19, 2003 #15
    This summer I worked with a Van de Graaff accelerator. We were able to accelerate protons and alpha particles to 2.5 MeV. Basically, it's just a Van de Graaff generator that charges up to about 2x10^6 V and accelerates the particles from a plasma that gets struck by an RF magnetic field. They go through a bunch of equipotential plates, basically round metal plates with holes in their middles that are connected by resistors so that they step down the voltage accumulated on the dome. To keep the dome from sparking over to the outer container, it's pumped down, then filled to low pressure with SF_6. There's a relatively long beam line that's pumped down to high vacuum with a sample chamber. We did some Rutherford Backscattering Spectrometry and some nuclear reaction analysis.

    There are also some smaller accelerators. At the University of North Texas, where I was this summer, they have a Cockcroft-Walton accelerator. This one's small enough that it could fit in a relatively large basement. Good luck with the electric bills, though. Accelerators eat power pretty ravenously.

    Just my 2 cents.
     
  17. Jan 21, 2004 #16
    Can you go into more detail as to materials, production and use? Id appreciate it. Im interested in designing one myself, bu i need more general info
     
  18. Jan 25, 2004 #17
    So what would you do with just a cyclotron (assuming you’ll build it, and you’ll willing to pay electrical bill for it’s el. Magnets, nevertheless Lawrence would be proud on you ;))? You need some detecting equipment, what about that, and what can you really do with homemade cyclotron (you can’t achieve energies needed for experiments you would like to conduct anyway)…

    Thing with that cloud chamber could be interesting… has anyone of you built it or saw homemade specimen (at least you’ll pass without scary el. bills)…

    Anyway I’m interested what effects are being used for detections of processes, experiments, globally everything happening in modern hi-energies accelerators?
     
  19. Feb 16, 2004 #18
    Cyclotron Boy indeed...

    I have to admit that this is a pretty bad trolling here, but I just wanted to let Warren know that I am still alive and around. I happened to see this message in the forum, and had to respond. I do not have cyclotron blueprints or schematics. However, I am writing a rather involved book on the subject of designing and building a particle accelerator in your garage or basement. I have quite a bit of stuff down already, and it is not finished. Anyway- it is certainly possible for the advanced tinkerer to create a particle accelerator capable of nuclear interactions. While I cannot design a machine for people, I can provide guidance. So, if someone wants help or advice in designing a machine of their own, please feel free to email me or post questions.

    The name "Cyclotron Boy" stuck. It is my /. name, and now my physics forums name. Boy, the science fair brings back memories. Good times, good times.

    And the website is http://www-personal.umich.edu/~mrniell/research.html [Broken]

    -Fred
     
    Last edited by a moderator: May 1, 2017
  20. Feb 16, 2004 #19

    chroot

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    FRED! CYCLOTRON BOY!

    Wow, it's AWESOME to have you here! There is no doubt that you were the most feared (and admired) presenter at the ISEF the years I was there. I have to say I'm embarrassed that, as a lowly sophomore in high school, I was afraid to even introduce myself to you!

    It's great to have people of your caliber here on physicsforums. We have a lot of late high-school / early college kids here, and your stories and successes will inspire and motivate many. I hope that you'll stick with us and enjoy the forum!

    (And I'm personally glad to hear you didn't take "cyclotron boy" as an insult, because it most certainly wasn't!)

    - Warren
     
  21. Feb 25, 2004 #20
    Well I'm quite entirely sure about Fermilab and CERN but I use to work in the computer department of the NSCL at MSU (www.nscl.msu.edu) and I saw most of the detection equipment they used in their experiments. For gamma ray detection, they used an array of segmented germanium crystal detectors set up in whatever geometrical pattern they needed. For beta decay they used silicon detector arrays that were about the size of a post-it note. They had a couple of large neutron detectors. One used a liquid scintillator and photometers and the other much newer one used a plastic scinillator that was formed into horizontal waveguides, had photometers attached to each end and were stacked into a large block. They hadn't officially used it (it was in the process of testign) when I left. They also had a few smaller neutron detectors that used a liquid scinillator. They also had a NMR beta detector and a few spectrographs. Overall it's a rather impressive place.
     
  22. Feb 27, 2004 #21
    Cyclotron Effeciency...



    Cyclotron Boy, I am inquiring as to what the Power Effeciency Rating is of your cyclotron design.

    I am inquiring as to what the total Power Input is versus the total Power Output of the resulting particle beam?

    What is the total Power Input?
    What is the total Power Output? (particle beam)

     
  23. Feb 27, 2004 #22
    Efficiency

    Orion,
    The cyclotron is by modern standards, an efficiency anomaly. It is not too terrible. Most of the inefficiency comes from the magnets. At the peak, I was able to get 40 microamps of protons, at about 100keV. So this is about 4 Watts of beam output power. On the input, the magnets used 2.2kW, and the RF amp used about 550W. The vacuum pumps ran at about 500W for the roughing pump, and 100W for the diffusion pump. The assorted test equipment and measurement tools took probably another 300-400W. So all told, it was somewhere around 3.2kW. So the overall efficiency is in the neighborhood of 0.125%.

    By comparison, FNAL uses somewhere in the neighborhood of $18Million dollars in electricity. The overall beam current is on the order of 1x10^18 protons / hour, and the overall energy is about 1TeV for protons and antiprotons. This is about 0.5MW of beam energy total. The lab probably uses 30MW/hr to get to the store, which takes about 10 hours to build up to the full beam current. This means about 0.5MW/300MW = 0.16%, and they're using superconducting magnets!

    A most interesting thing you bring up is that the system as a whole required more power than I could get out of a single circuit in my house. I actually had to run different systems on different circuits in the box. And yes, it really did "dim the lights" when I turned on the magnets. I had to inductively limit the inrush current from the main variac in the magnet power supply just to get the breaker from tripping.

    Fermilab has 2 power substations coming into the site with 200kV transmission lines to feed the machine. It turns out they can't run off of just one circuit either...
    :wink:
     
  24. Feb 27, 2004 #23

    ZapperZ

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    I don't want to dampen people's enthusiasm on here, but I thought I should point out something after silently following this thread for some time.

    I need to point out one thing that people may be overlooking - SAFETY. This applies to both ring accelerators and linear accelerators. I'm guessing that whatever you intend to build in your basement or garage isn't going to get to the same level as what most accelerator research facilities would get to. But you still have to keep in mind that accelerator facilities are shielded for one very obvious reason - that there are a number of possible sources of radiation. This can be from the charged particle beam itself (UV up to hard x-rays), and from when the beam either gets dumped, or hits any material. While keV electrons may not be a big deal, keV protons are. And as soon as your electrons get to MeV level, you'd better have ample shielding or you may want to consider a dosimeter count to see how much above background radiation you're actually getting.

    But again, as I've said, you may not get close to the energy scale that you should be worried about if you're building this at home with commonly-available material. But you should at least be aware of this aspect of the risk in case of some odd chance that you get close to the safety limit.

    Good luck.
     
    Last edited: Oct 7, 2010
  25. Feb 27, 2004 #24
    Safety

    I couldn't agree more. I never operated my machine without adequate shielding, and I always had a TLD dosimeter badge, a quartz fiber dosimeter, and a geiger counter going for each experiment. I was making quite a few medium-energy X-rays (75-100keV) from within the machine, but also multi-MeV gammas from the particle interactions my protons were creating. The numbers are small, and in 3 months I took somewhere around 20mRad. This is a kind of high for amateur use, but in accelerator work, it isn't all that bad. By comparison, in an 11 hour subsonic jet flight from Chicago to Paris, you would receive a dose of 3.4mRad. Another comparison is that a lumbar spine X-ray is done with 100-175keV X-rays, and the integrated dose is typically 350mRad.

    My cyclotron did not extract the beam. Also, the walls of my vacuum vessel were 1/4" stainless steel, so the high energy electrons weren't too much of a problem. The X-rays were high enough E to make it out without any problems. The top and bottom of the chamber were made if 1/4" glass, and the glass took a lot of radiation over the 3 months. After that time, the glass did discolor and turn brown from the intense X-ray beam. I also found some 2'x3' 1/8" lead sheets at a local scrap yard that made for perfect bendable, movable shielding.

    One thing to keep in mind, even when playing around with mild X-rays, is that the corneas and skin are very sensitive to any ionizing radiation. Betas and accelerated electrons are particularly notorious for inducing catarracts and blindness without adequate shielding. Skin burns are very common with inadequate and inappropriate safety procedures.

    So- if you plan to build a machine in your garage, be sure you know something about radiation, electrical, and general safety before you start anything.

    -F
     
  26. Feb 28, 2004 #25

    chroot

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    Cyclotron Boy, :wink:

    Can you tell us more about how you learned how to plan and assemble all this equipment while still in high-school? Maybe some suggestions on where other kids who might hope to follow in your footsteps should go to learn?

    - Warren
     
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