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Production of C14 in the upper atmosphere

  1. Feb 25, 2009 #1
    I'm having some doubts about the standard idea of N14 + energetic Neutron > C14 + Proton.

    Is it possible that the generation of C14 could be a reverse form of the C14 beta decay to N14, initiated by the relativistic electrons entering the ionosphere in the auroras?
    An endothermic Electron Capture by a ionic N14 nuclear proton? Either an electron of near the kinetic energy of the beta particles produced by C14 decay, or an inner shell electron after the nucleus of the N14 is excited by a bremstralung photon of appropriate energy?
     
  2. jcsd
  3. Feb 25, 2009 #2

    clem

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    The weak interaction is much weaker than the strong interaction.
     
  4. Feb 26, 2009 #3
    So you are weakly interacting with this question? Please clarify. Is there a strong interaction with other parties relevant to your response?
    ;-)
     
  5. Feb 26, 2009 #4

    alxm

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    Why exactly, are you doubting it? Other than that you've got your own idea?

    Basic thermodynamics is enough to say that an endothermic reaction of 0.16 MeV isn't likely to happen, or to be very stable if it does.

    It's never been observed AFAIK either.
     
  6. Feb 26, 2009 #5
    I guess my curiousity has been activated by other references to reversal of beta decay reactions in other enviroments. And I think that it is a valid point that the C14 stability before beta decay, halflife almost 6000years: is an unusually wide shelf. Perhaps not so unlikely to occasionally be landed on.
    Also I am curious about what nuclear transformations may be happening in similar places. Like for example the inner Jovian ring, where outer planar rings appear to be feeding into a toroidial ring in the geometry of the intense radiation enviroment of Jupiter's radiation belt with its ultra relativistic electron, and high energy proton populations.

    Back to the C14 thing. I suppose that another potential production path may be spellation by radiation belt protons. Via: O16 + fast P > c14 + He3. The energies of Protons in the inner belt have upper limits of hundreds of MeV at least. Particularly in the sth atlantic or se asian mag anomalies these could be initiating nuclear reactions.
    I also have mental knots at the Idea of enough incoming Neutrons to justify N14 + N > C14 + P when the half life of free neutrons is only about 10min.
     

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  7. Feb 27, 2009 #6
    Obviously my brain slipped out of gear as I typed that. O16 + fast P > C14 + 3P
    Also possible may be :
    (natural abundance 0.366%) N15 + fast P > C14 + 2P
    (natural abundance 0.038%) O17 + fast P > C14 + He3 + P (or C14+ 2P +D)
    (natural abundance 0.2%) 018 + fast P > C14 + He4 +p (or C14 + He3 + D or C14 + 2D + P)

    Doesn't look like Relavitistic electron capture is common except in Neutron star formation. Tho I have seen references to resonance peaks in the region of 0.1-10MeV for electron capture by nuclear protons. Just the sort of range of electron energies in the radiation belts.
     
  8. Mar 5, 2009 #7
    perhaps the intricacies of nuclear shake and bake in the atmospheric fringes of the magnetically active planets deserves a new thread with a more juicyer title. This one seems to be repelling discussion like it has too much equal polarity with the local monopoles. Lol
    Anyone bother to look at the charts I posted above? 100 thousand relativistic electrons per cubic cm. 100-1000 protons in the 1-many hundreds of Mev range per cubic cm? Thats a lot of flux when you work out the visitors to a sqcm per second. I think its worth considering what 3 000 000 000 000 000 electrons per sqcm per second in the MeV+ range might be doing. Plus those protons. What alchemy could this be achieving in our outer atmospheric layers?
    And the more extreme examples like jupiter and uranus even more so. Rare nuclear reactions such as reversed beta decays, may produce significant results, in the ambient high energy enviroments of these regions, with particle fluxes this intense.

    Whats the watts per sq cm of those average 7MeV electrons at 3 x 10^15 per sqcm per second? Anyone want to post a calc showing how to work out that?

    Seems pretty important to our understanding of the nature and origins of the matter in our stellar backyard to consider these possibilities.
     
  9. Mar 5, 2009 #8
    I'm getting over 3 kilowatts per sqcm as an energy flux from those electrons. At typical nuclear reaction level quanta for the electron energies that make up that total. Is there some kind of political problem that is preventing peoples engagement with this subject matter?
     
  10. Mar 6, 2009 #9

    Vanadium 50

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    I suspect that most people have seen your reaction to clem's (correct) observation which you mocked, and alxm's (correct) observation, which you didn't really address, and the fact that you posted four consecutive messages without a response and come to the conclusion that you are more interested in a monologue than a dialog.

    When you post that you don't believe in the standard explanation of C-14 production, but that you do believe the energy from electrons impinging on the upper atmosphere is 20,000 times greater than that from sunlight, it only reinforces it.
     
  11. Mar 15, 2009 #10
    Not at all Vanadium. Thank you for the attention, but the energy density of the particle fluxes in the belts is not comparible to what is able to flow in in less temporally constricted processess. How do we define "correct" whether observational or belief based here anyway?
    I'm just at this point looking at lumps in the fabriuc of reality that I choke on when I come across such undigestable matters such as the standard MIT resource material of the energy fluxes in the VA belts that you Vanadium so succinctly point out as 20000 times more energetic than solar input on our planetry surface.
    I'm just looking for some clarity in the understanding of what we know.
    No game of winners and losers interests me. thats monkey stuff.
     
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