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Accelerating Neutrons

  1. Apr 29, 2008 #1
    Hi, is there anyone that can tell how neutrons are accelerated for experimental use.
  2. jcsd
  3. Apr 29, 2008 #2
    Hi, and welcome to PF

    neutrons basically can not be accelerated. You need a neutron source. Roughly, you take huge nuclei, throw bunches of high-energy (so-called spallation) smaller guys, then somehow getting rid of anything charged you end up with only neutrons going out of your source.

    http://www.mrl.ucsb.edu/~pynn/primer.pdf [Broken]
    Last edited by a moderator: May 3, 2017
  4. Apr 29, 2008 #3


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    Neutron beams may be generated 1) from nuclear reactors, but there is a broad spectrum of energies, 2) from fusion reactions, e.g. d+t -> alpha (3.5 MeV) + n (14.1 MeV), or 3) from spallation (p,n) reactions, in which accelerated protons are used to knock neutrons out of nuclei.
  5. Apr 29, 2008 #4

    Vanadium 50

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    That said, what people often do is accelerate beams of deuterium (one proton + one neutron) and beams of protons, and subtract the off the proton measurement. It's not quite the same as a beam of neutrons, but it's close.
  6. Apr 30, 2008 #5
    Thanks for the answers.
  7. May 2, 2008 #6


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    You can accelerate deuterons into a thin target that strips the proton, leaving a high energy neutron beam.
  8. May 3, 2008 #7


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    Do you know what kind of targets one can use for this purpose?
  9. May 3, 2008 #8


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    This paper describes generating a 50 MeV neutron beam:

    Higher energy neutron beams are now produced at Los Alamos. A paper with this beam is:
    Phys. Rev. C 75, 031001 (2007). They describe it as:
    "At the LANSCE-WNR facility at the Los Alamos National
    Laboratory, a pulsed neutron beam is produced by an 800-MeV
    proton beam incident on a 7.5-cm-long water-cooled tungsten
    spallation target."
    This neutron beam experiment finally confirms theoretical predictions from 1972.
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