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The quantum solar haiku

  1. Aug 29, 2003 #1

    marcus

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    the classical japanese haiku form is 5-7-5
    we should invent a new form called "quantum haiku" which is 5-4-5 :wink:

    the sun makes all its energy by a process called "proton-proton chain" which goes like this---it's a bit like a haiku

    p + p ---> pn + positron + neutrino
    pn + p ---> ppn + gamma
    pn + pn ---> ppnn + p + p

    This happens in the core of the sun, the central 20 percent or so.
    Virtually all our energy, including that in Ben and Jerry's ice cream, comes from this three-line sequence of reactions. Notice the gamma-ray in the second line----it's the original sunlight.

    All sunlight starts out as gamma (X-rays) at the core of the sun,
    it just gets mellower as it percolates out to the surface, and like as not, the neutrino you see there is the missing solar neutrino that they just found the right number of after all.
    In this style of writing, "p" means proton and "n" means neutron, so p represents a Hydrogen nucleus, pn stands for a Deuterium nucleus, ppn stands for a Helium-3 and ppnn for a Helium-4.
     
    Last edited: Aug 29, 2003
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  3. Aug 29, 2003 #2

    marcus

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    the CNO process in more massive stars

    Not all stars make their energy in the same way.
    Stars of one solar mass or less are all doing the proton-proton chain---according to the revered haiku just mentioned

    But in stars of two solar masses or more a faster CATALYZED fusion process predominates, called the "CNO process" which sounds faintly like a railroad back in the steam locomotive days.
    And this process uses Carbon, Nitrogen, and Oxygen nuclei as catalysts----the protons stick to them and get fused and come off as helium: same result but it goes faster.

    CNO only works in more massive stars because it needs a higher threshhold temperature to get started.

    So if you see Orion, off to the left about knee-high there is Sirius and the light coming to you from that star was originally made by CNO, for instance. A lot of the stars you see are massive bright ones that use CNO. So by day pretty much all the light we get is proton-proton light but in the night sky quite a lot isnt. Its made a different way.
     
    Last edited: Aug 29, 2003
  4. Aug 29, 2003 #3

    marcus

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    spelling out the CNO

    It is not clear the CNO process needs to be
    spelled out. You could figure out for yourself how it goes in broad outline form anyway---
    you start with a standard Carbon-12 and stick protons onto it
    until you have stuck four on.
    Then they fall off as a Helium-4, and you have your C-12 back again.

    In the meantime human words intervene, we call certain things nitrogen nuclei and certain things oxygen nuclei, because of
    the role they play in our chemistry

    But these are just what temporarily results from sticking protons onto a C-12-----they dont have time to participate in chemistry and the human names for them are not all that relevant in the present situation: namely the core of a massive star.

    So here is how catalyzed fusion goes:

    C-12 + p ---> N-13 + gamma
    N-13 ---> C-13 + positron + neutrino
    C-13 + p ---> N-14 + gamma
    N-14 + p ---> O-15 + gamma
    O-15 ---> N-15 + positron + neutrino
    N-15 + p ---> C-12 + He-4
     
    Last edited: Aug 29, 2003
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