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Range of Neutrons in Matter

  1. Sep 7, 2011 #1
    Hello everyone,

    Is there such a thing as range graph as a function of the energy for the neutrons in matter? I have been looking for it all over the web, but I just found the cross sections plotted when the neutron comes from different reactions. Is there a more general graph that discribes the distance a neutron would travel in different materials as a function of its energy?? Thanks in advance
  2. jcsd
  3. Sep 7, 2011 #2
    Neutrons do not have a range in matter the way charged particles do. It is theoretically possible for neutrons to diffuse through any shielding, though it is unlikely if the shield is thick enough. However, neutron attenuation is roughly exponential.
  4. Sep 7, 2011 #3
    Hey probably should have been more specific. I do realize that neutrons won't interact with matter in the same way as charged particles. However I would like to know what is the probability that a neutron would be detected, for example in a scintillator or a thin material. I think this is possible, even if the rate is extremely low. So that is why I was asking if there exists kind of a "Bethe" plot for neutrons. Thank you.
  5. Sep 16, 2011 #4


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  6. Sep 16, 2011 #5


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    The range depends on the neutron energy and the type of material. Neutron detectors would contain hydrogenous material because the neutron could lose almost all its kinetic energy to a proton, or a large portion thereof.

    The range depends on the macroscopic absorption and scattering cross-sections which depend on the isotopic vector of the media through which the neutron passes. Cross-sections of nuclides are also energy dependent.
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