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Neutron imaging

  1. Jan 27, 2009 #1
    how plausible is it to image a single molecule using low energy neutrons? I was thinking it might be possible to build something similar to an interference microscope in order to accomplish this however i'm not entirely sure.

    I was thinking of doing a little research project on the mechanics of such a scope and was interested in any thoughts.
  2. jcsd
  3. Jan 27, 2009 #2


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    It is very difficult to build neutron microscopes (although they do exist) simply because you can't use electromagnetic lenses (which is how e.g electron- and ion-based microscopes work) to focus the particles; this is the reason for why existing microscopes have very low resolution.
    Another issue is that neutrons are very heavy and carry a lot of momentum so presumably you would always run the risk of destroying the sample you were looking at, at least if you were really trying to look at an individual molecule (neutron scattering is routinely used to determine the structure of complex molecules, but that is a very different mechanism)
  4. Jan 27, 2009 #3


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    It's not plausible, basically for the reasons stated by f95toli. The individual neutrons would scatter off the nuclei, if not absorbed. The scattered neutrons would have to be detected, but as far as a detector would be concerned, the neutrons would appear to come from a point source. Neutrons can only be detected by being absorbed, since they don't interact electromagnetically with atoms.

    Neutron radiography works like X-ray radiography, in that it is the neutrons which pass through the object that are detected (absorbed) by an image target. The neutrons are absorbed by the atoms (nuclei) in the target, and is then the gamma emissions from the target which render an image on a photographic film or phosphor.
  5. Jan 27, 2009 #4
    wouldn't low energy neutrons interfere thus producing an interference pattern? I see the implausibility due to optics (something that could possibly be overcome) or more importantly beating the crap out of your molecule by bombarding it with neutrons.

    if the neutrons were of sufficiently low energy though they would not be prone to absorption correct? and instead would scatter off the nucleus?
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