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I'm looking to build a small particle accelerator for a science fair

  1. Sep 21, 2011 #1
    Oddly enough, it's for a science fair :)

    Anyway, I joined the Science Club at my high school earlier today and I learned that we'll be entering our a science fair, winners of which will go to regionals. I read Michio Kaku's (forgive any misspellings) book Hyperspace and it somewhat motivated me to build one...and the science fair will be my reason. Note: we're expected to bring in the results, processes, and pictures rather than the project itself.

    What source of particles should I use? Something radioactive would be fun...however, I have no desire to have an awkward conversation with the CIA with skeptical nods and "Mhms" between sentences. I'm not entirely sure what I should use. Granted, I haven't done much research

    I'm only looking to accelerate to whatever speeds I can reasonably reach. I don't want it to be very big (a football field is a little to much), but at the same time I want some reportable results. If it could fit into a workshop/garage (it's about 20ft from door to end, so a radius of 5ft should allow plenty of room for movement) I would be a very happy person, but I could do with smaller.

    I'm also concerned about power usage. I don't intend to do anything on the same scale that Kaku did. The size of his experiment shorted the power in his home and his was around the size of a football field. I expect to not come too close to that, but it is still a concern of mine. If anyone had any instructions on how to build a generator (a Van de Graff generator would suffice) I would be pleased...if anyone knew a price range on pre-built ones I would be elated, but I don't have a problem DIYing the whole thing.

    Another thing I'm concerned about are the magnets, but let's not get ahead of ourselves here. I'll need the above information first before I worry about anything else.


    Note: I may not be able to do this. I've already emailed the head of my region's science fair about my little project for specific rules pertaining to my experiment. I was unable to find anything on the website (most of which dealt with regulations about living experiments), and I'm waiting with bated breath for my restrictions.


    Thanks in advance.
     
  2. jcsd
  3. Sep 21, 2011 #2

    Drakkith

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    I'm a little hesitant for someone like yourself to be working with high voltages and vacuum pressures. The high voltage alone can easily kill you with just a single mistake. Do you have ANY experience with electronics before this?
     
  4. Sep 21, 2011 #3
    This.

    Maybe you could start smaller, like a railgun?
     
  5. Sep 24, 2011 #4
    Sorry for the delayed response. I myself do not have much electrical experience, however I know that my dad does (we remodeled a room next to our deck and he rewired it up to code...by himself) and I intend to have him supervise my electric antics. I also know the safety precautions (e.g. DON'T TOUCH IT) and I have a fair bit of common sense when it comes to things that are lethal.
     
  6. Sep 25, 2011 #5

    Drakkith

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  7. Sep 25, 2011 #6
    The easiest option would be to just use electrons. They can be created with a hot wire (light bulb filament)
    If you want to use radioative materials to create e.g. positive helium ions - also known as alpha particles, you could use polonium 210. A small amount of that stuff can be ordered from amazon. Just search for "static master refill" on amazon.com and you should find it. It's a very strong alpha source (250 microcurie = 9 million decays per second). In fact it's so strong, schools wouldn't get a permit to use it in physics class. It's intended to be used for neutralizing static charges. However if you use that you don't need high voltage since the alpha particles will already have 5MeV when they are produced i.e. they move as fast as if they had been accelerated by 5 million volts.
     
  8. Sep 25, 2011 #7

    Drakkith

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    I seriously do not recommend using any radioactive materials at all. Not only are they hazardous to yourself, a simple mistake or mishandling could expose others as well. And even if it was such a tiny amount that it effectively poses no hazard, I guarantee you that anyone that hears they were exposed to ANY amount of radiation will flip out and probably cause you serious legal problems.
     
  9. Sep 25, 2011 #8
    If you are afraid of legal issues you could also just use a piece of wood. In 1kg of normal wood there are a few thousand decays per second most of which are due to potassium 40. A few percent of these decays even produce antimatter (positrons).
     
  10. Sep 25, 2011 #9
    just wondering. lightning produces antimatter above the clouds. if it were possible to make antimatter right in the accelerator. antimatter anhilates! but is it possible to make antimatter at home, even theorethically.
     
  11. Oct 2, 2011 #10
    Sorry for my delayed response (again). In any case, thank you Zoidberg for that information :) I'm leaning more towards simply using electrons (smaller mass and easier to obtain) and I was looking through Yahoo! answers and I found an interesting answer. Here's the link:

    http://answers.yahoo.com/question/index?qid=20080816223721AAoJyyL

    Is this accurate? I was tempted to take this and go with it, but I would like a bit of confirmation first. After all, no one likes to build a machine only to realize it doesn't work.

    Again, sorry for my delayed response.

    EDIT: I also found some information here: http://www.ifpan.edu.pl/firststep/aw-works/fsII/alt/altineller.pdf

    Is this credible as well?
     
    Last edited: Oct 2, 2011
  12. Oct 2, 2011 #11

    OmCheeto

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    Those look really complicated.

    I have one sitting in my living room you can have. Actually, looking around, I have 4 sitting in my living room! Gads, I am a hoarder.

    I'm pretty sure that if you could explain the theory behind how they work, and brought in an old 12 inch black and white screen TV made in the 70's, that would really impress the teacher, and you'd get an A. With a few demonstrations with magnets, and full color glossy diagrams, of course.

    I'm afraid I can't help you with how they work though. How does heating up a filament eject electrons? And how are they accelerated? Are those really electrons that I see when the screen lights up? How would you prove that they are electrons? Does deflecting the (supposed) beam of electrons with magnets near the screen mean anything? How would you measure the deflection of the beam? What speed are the (supposed) electrons traveling at? How could you measure that with just a magnet? What are the internal components in a TV tube that no one really knows about? What happens to the (supposed) electrons after they hit the screen? Do they just sit there? How many are there? How could you count them? Is there even a way to count them? What's the relationship between magnetic flux, electron velocity, and electron deflection?

    Ahhhh!

    hmmm.... The 'famous' guys at Fermilab probably didn't build their own accelerator. They just did the experiments.

    ps. Do not attempt to disassemble an old TV tube. They will im/explode, and you will most surely die.
     
  13. Oct 2, 2011 #12

    Vanadium 50

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    First, anyone who thinks you need "appropriate low vacuum greasy stuff" doesn't know what he is talking about. Second, if you can't tell that he doesn't know what he's talking about, that means that you don't have the technical know-how to pull this off.

    This is fraught with hazards, and if you don't know what you are doing, you are likely to hurt yourself or others. You need to pick another project.
     
  14. Oct 3, 2011 #13
    Or just buy some salt substitute which is potassium iodide.
     
  15. Oct 3, 2011 #14

    Drakkith

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    I'd have to say that a CRT is probably the perfect thing for you. You wouldn't even need to disassemble it or anything. Just have it there, maybe take the case off if you wanted to detail the interior. Explain how it all works and stuff and you should be good. I mean how many people realize that a plain old TV works on similar principles that the Large Hadron Collider uses. Accelerated subatomic particles confined and guided by magnetic fields!
     
  16. Oct 3, 2011 #15

    OmCheeto

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    But if you take the case off, I'd advise covering the entire thing with an old fish tank or something. (If you plan on plugging it in that is.) Someone might want to touch something while saying; "What's this?"

    http://en.wikipedia.org/wiki/Flyback_transformer" [Broken]
    20,000 volts, is a lot.

    ps. I also have an old fish tank on my front porch that will fit perfectly over one of the 5 particle accelerators I have in my living room.
     
    Last edited by a moderator: May 5, 2017
  17. Oct 3, 2011 #16

    Drakkith

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    True, that would be a good idea.
     
  18. Oct 3, 2011 #17
    Buy a CRT monitor and... ta-da! Particle accelerator.

    EDIT: Dang-it! Someone beat me to it.
     
  19. Oct 5, 2011 #18
    Not very helpful today, are we?

    I'm being serious about this. I'm looking to build a linear particle accelerator and I'm looking for some advice. There's a reason I'm looking for help: it's because I don't want to screw this up. I can do this with or without your help; however, I would like help so I can speed up the process. If you aren't going to be helpful tell me now :)
     
  20. Oct 5, 2011 #19

    Vanadium 50

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    Please reread the PF Rules on dangerous activities. If you have decided to do something dangerous "with or without our help", you are too immature to do it safely. We cannot help you injure (or worse!) yourself and others.

    If someone said "I want to jump out of an airplane holding a bedsheet over my head as a parachute - what color is best?" we wouldn't help them either. It would not be doing them a favor.
     
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