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Is it possible to fuse more than two atoms at once?

  1. Jan 6, 2016 #1
    I'm writing a paper for my teacher, not an assignment, just because I was interested in the topic. I've searched a lot of websites, but most only talk about fusing two atoms, and not saying if it is possible to fuse more than two at the same time.
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  3. Jan 6, 2016 #2


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    Can you be more specific? The sun certainly fuses many atoms at the same time. Mankind had only fused atoms in H-bombs so far. (Maybe a few single ones in labs). There are surely many atoms fusing at the same time during the detonation.
  4. Jan 6, 2016 #3
    Yes it is
  5. Jan 6, 2016 #4
    I think the OP means can it possible for three or more atoms to fuse into something instead of just two.
    I think that is possible but very unlikely, because the circumstances for just two atoms fusing have to be exactly right.
    For the circumstances to be right so that three atoms fuse is possible I think, but is a very low probability and almost certainly not a situation which could be easily engineered.
    Last edited: Jan 7, 2016
  6. Jan 7, 2016 #5
    Fusing 3 atoms is very common and vital, for some definition of "at the same time". Triple alpha. For some definition of "at the same time", because the half-life of Be-8 is in the region of 10-16 s, not in the strong interaction timescale of 10-22 s.
  7. Jan 7, 2016 #6


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    To extend the explanation: As snorkack noted, the timescale of fusion processes is incredibly short, like 10-22 seconds. And nuclei are extremely small, of the order of 10-15 meters. The probability that three nuclei come together at the same place and the same time (within those scales) is negligible. It would require conditions that lead to rapid (2-nuclei) fusion or even disintegration of the nuclei long before three-nuclei fusion would become relevant.
    The triple alpha process has relaxed conditions as the intermediate Be-8 has some reasonable lifetime, but it still needs very high temperatures and densities to occur.
  8. Jan 10, 2016 #7


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  9. Jan 12, 2016 #8
    Two protons have never been observed to fuse either.
  10. Jan 12, 2016 #9


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    Helium-2 which consists of two fused protons is a very unstable isotype of helium with a short half life, but it has probably been observed on multiple occasions and has also been inferred from the chemical makeup of stars, which would be different if this possibility were not considered. While it is observed in the decays of heavier atoms, the fusion of two protons is an intermediate step in its formation.
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