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Photo fission question.

  1. Dec 7, 2013 #1
    I was talking to a person that studies photo fission and i asked if I could shoot a couple of lower energy photons to cause fission. But he said it wouldn't work I would need 1 high energy one.
    Im not completely sure why this wouldn't work. Does the photon have to get absorbed at one point.
    Not sure how that works. What if I shot a neutron and a photon at the same place, and both together had enough energy to induce fission. I dont know that much about photo fission.
  2. jcsd
  3. Dec 7, 2013 #2
    A low energy photon wouldn't be absorbed by the nucleus. It would bounce back
  4. Dec 7, 2013 #3


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    Gold Member

    Your answer relies in the "quantum" of the quantum mechanics!
    In quantum mechanics,whenever there is a potential,there are energy levels.Which means the system can't have any energy and only the energies equal to the energy of the levels are allowed.You've probably heard it before,when studying about the electronic structure of atoms.Electrons have discrete energy levels.
    Nuclei also have energy levels and protons and neutrons have to be on one of this levels and so the energy of the Nuclei themselves are discrete.
    If a photon's energy is somehow that isn't enough to excite the nuclei to the next allowed state,it can't be absorbed and because fission happens after going to one of those excited states,only photons with certain energies can cause fission.
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