Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Neutron Generators

  1. Jan 9, 2010 #1
    a) I need a simple description of how a Neutron Generator is built and how it works.

    b) Where can I see a picture of what a Neutron Generator looks like?

    c) What is a Plasma Focus (PF) Neutron Generator?

    d) Is PF the only type of Neutron Generator or are there other types?
  2. jcsd
  3. Jan 9, 2010 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Is this a homework problem?

    Two common methods would the (d+t) reaction using accelerated deuterons on a tritiated target, and an (alpha, Be) reaction in which alpha particles from a radionuclide of a Pu, Po or Ra isotope bombard Be nuclei.

    There are other methods.
  4. Jan 9, 2010 #3
    Thanks for the answer. I am familier with isotopic sources using the (alpha,n) reaction. It is the (d+t) you mention that I don't understand. How are the deuterons accelerated? Is he (d+t) a portable devise?
    BTW this is not a home work problem.
  5. Jan 9, 2010 #4


    User Avatar
    Staff Emeritus
    Science Advisor

    For the d+t reaction, there are two possibilities. One is to electrostatically accelerate deuterons across a potential difference of a few keV. The deuterons then stike a triton (nuclear of tritium) which could be in the form of a metal hydride. This is the principle of a neutron howitzer.

    Another possibility is to heat a mixture of deuterium and tritium gas until is ionizes into a plasma. At sufficient temperature (with a reasonable density) deuterons and tritons will fuse, and in fact one might obtain d+d fusion, with production of He3+n or t+p. This is the principle behind magnetic confinement (low density) and intertial confinement fusion (high density).

    The third alternative is a hybrid of the other two, using electrostatic fields to accelerate deuterium/tritium gas into a central confinement volume in the presence of a magnetic field.

    Example - http://www.physics.ucla.edu/icnsp/PDF/bromley.pdf
  6. Jan 9, 2010 #5
    Thanks again. Thanks so much. If I may ask further. Is a battery connected to the Neutron Generator to create the potential difference that accelerates the deuterons? Do you have a picture of one of these devises?
  7. Jan 9, 2010 #6


    User Avatar
    Staff Emeritus
    Science Advisor

    Batteries are not used. Rather high voltage power supplies would be used.

    Here is an article with a schematic.

    Fusor time arrangement

    A patent - Neutron tube comprising an electrostatic ion source
  8. Jan 9, 2010 #7
    Thank you Astronuc. The principle and method of operation is now clear to me. With the drawings you indicated, I can visualize the equipment. I guess the only question left now is how "Plasma Focus" fits into all this.
  9. Jan 9, 2010 #8
    Last edited by a moderator: Apr 24, 2017
  10. Jan 9, 2010 #9
    Thank you Bob. I have just read the thermo article. very informative - especially the simple sketches and the photo which shows exactly how the NG looks.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook