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Neutron bombardment of paraffin

  1. Apr 1, 2013 #1
    When paraffin wax (or borated paraffin) is bombarded with neutrons, what does the paraffin emit? (If memory serves me correctly I think it emits protons...?) Also what are typical energies that the emitted particles have?
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  3. Apr 1, 2013 #2


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    Bombarded with neutrons of which energy?
    Boron and hydrogen are good absorbers for low-energetic neutrons, and will release alpha and gamma radiation.
    High-energetic neutrons can produce all sorts of hadrons in the collisions.
  4. Apr 1, 2013 #3
    Say the neutrons created from alpha irradiation of either beryllium or aluminum
  5. Apr 1, 2013 #4


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    Mostly, paraffin and the H atoms it contains are considered to be a good neutron moderator. That means repeated elastic collisions. There's also an appreciable cross-section for capture, formation of a deuteron and release of a gamma.
  6. Apr 1, 2013 #5
    So paraffin bombarded with neutrons from an alpha irradiated beryllium/aluminum source will produce gamma and a deuteron? What would be the approximate expected energy of the deuteron?
  7. Apr 1, 2013 #6
    Well how do we know?
    You didn't say the energy parameters for the input energy or the "alpha irradiated beryllium/aluminum source"

    Surely the output energy will not be bigger than the one that went in , ofcourse if there doesn't start a chain reaction which is not the case with paraffin.
    So the output will always be somewhere less than the input not also the output energy will be divided among the products of the outcome ( gamma, deuteron etc.)
    Now if you would give us some numbers I'm sure there will be some math fanatics here to give you the approximate energies.
  8. Apr 1, 2013 #7
    Yeah sorry about all the abstracts, I'm just asking theoretical questions. Has anyone done experiments with neutron bombardment of paraffin using alpha irradiated beryllium/ aluminum source? Maybe that could give me a better idea of the energies involved.
  9. Apr 1, 2013 #8

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    I think the OP is thinking of elastic scattering detectors, where the neutron comes in and elastically scatters with a proton in the paraffin. The proton is then detected. Since m(n) is close to m(p), you have a phenomenon like Newton's Balls.
  10. May 2, 2013 #9


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    Well, except that the scattering is usually not ---><---- head on like in Newton's cradle.
    Most of the time it is at an angle. The proton gets some of the energy and the nuetron
    loses some.

    The recoiling proton probably does not go very far. It will scatter from the various
    things in the paraffin. So mostly it will just produce some dislocation effections in the
    wax, some heat, maybe some weird molecules due to the ionization.

    Mostly what you will see from neutrons on paraffin is some photons produced by
    capture events, at least at energies low enough not to be producing other stuff.
    If the energy is high enough you can start to see lots of others tuff.
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