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Linac energy

  1. Apr 23, 2013 #1
    Hi all, this is my first time posting.

    This may seem too vauge but could a 2m long linac accelerating electrons (with electron gun as source) achive 1.5MeV? I.e. Could it make positrons via pair production? (0.511MeV For electron same for positron plus a litle extra to be safe) asuming it uses quadropole and sextupole magnets (copper) liquid nitrogen cooled. Electrostaticly acelerated via muliple staged electrodes (max voltage=~100 000v). Thanx to you geniuses in advace
     
  2. jcsd
  3. Apr 23, 2013 #2

    Bill_K

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    The 2-mile long linac you may be speaking of was the one at SLAC, which achieved 90 GeV center-of-mass energy.
     
  4. Apr 23, 2013 #3
    i meant two meters. 1.5 Mev posible using only electrostatic aceleration?
     
  5. Apr 23, 2013 #4

    Bill_K

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    Sorry, my mistake. You're actually thinking of building a table-top linac?? Good luck generating and storing the positrons. Good luck getting the beams to collide. And don't forget to watch out for the radiation produced when the beams hit the backstop!
     
  6. Apr 23, 2013 #5

    mfb

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    1.5 MeV with 2 meters of separation is possible with electrostatic acceleration (but 3-4m would be easier), and you can use the 1.5MeV-electrons to do pair production afterwards. Focusing is neither necessary nor practical with such a small setup, I think. You just need a good insulation and a Van-de-Graaff generator. If you want to do something with the positrons, the setup will grow.
     
  7. Apr 23, 2013 #6
    thanks! I wasn't planning to do anything with the positrons yet. Thanks for not being harsh. If i may ask what target should i use and could i detect the positrons?
     
  8. Apr 23, 2013 #7
    oh, and could i use a flyback transformer coupled to a cfl circuit instead of a van de graff generator?
     
  9. Apr 23, 2013 #8

    mfb

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    As target: probably something where the electrons can produce high-energetic photons, and those can be converted to electron/positron pairs afterwards - a material with heavy nuclei? Gold is expensive, lead is toxic.
    This is nothing you should do at home. It is very dangerous, and probably illegal.
     
  10. Apr 23, 2013 #9
    i will check with my local police station. But is there any cheap way to confirm positrons have been produced? And how about tungsten for a target?
     
  11. Apr 23, 2013 #10

    mfb

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    The police station won't tell you how to avoid getting killed, or injured.
    There is. If you know enough to build such a device safely, you will know the answer to that question.
     
  12. Apr 23, 2013 #11
    but a device with a 100% acuracy that only detects positrons? And by the way, i always do my research once i know what to research. I am familiar with high voltage safty as i have built a jacobs ladder and tesla coil in the past. I do already have lead-impregnated glass for the hard radiation from a recycling company.
     
  13. Apr 23, 2013 #12
    so if you could just tell me the name of the detector needed. Please.
     
  14. Apr 23, 2013 #13

    berkeman

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    Pseudo Epsilon -- We do not allow discussions of dangerous activities here on the PF. This thread is closed. Please do not ask questions like this here again.
     
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