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Help - electron beams

  1. Oct 20, 2006 #1
    Hey guys

    Apparently I have to know how to find the energy of accelerated electron beams for a test, and I'm not sure how. Any help?

    I'm assuming it's talking about electron guns: I think this consists of a heated cathode which emits electrons via thermionic emission, and an anode which accelerates them. But how do you actually get the cathode and anode (i.e. what are the circuits and how does one make each electrode charged). Is the electron beam energy just the voltage between the cathode and anode multiplied by Q (=It)?

    Thanks, Jonty
    Last edited: Oct 20, 2006
  2. jcsd
  3. Oct 20, 2006 #2


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    The energy is e*V as you suspected, charge of electron times potential difference. The circuits to create a beam for an electron gun can be quite simple. Controlling the beam to do something useful as in a cathode raty tube is a bit more involved.

    http://www.matter.org.uk/tem/electron_gun/electron_gun_simulation.htm [Broken]
    Last edited by a moderator: May 2, 2017
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