The Oxygen to Carbon Ratio in the Solar Interior: Information from Nuclear Reaction Cross-Sections
Mass separation in the Sun may explain a serious difficulty that has plagued nuclear astrophysics for decades: Why the oxygen to carbon ratio in the Sun's photosphere is only two, O/C ≈ 2. After correcting for mass fractionation, the ratio of these helium-burning products in the Sun is much larger, O/C ≈ 9-10. The lower value, O/C ≈ 9, is probably more reliable. It is based on measurements of mass separation of stable noble gas isotopes in the solar wind over the mass range of 3-136 amu. The higher value, O/C ≈ 10, is based on a comparison of neutron-capture cross-sections and the abundances of s-products in the photosphere over the mass range of 25-207 amu. Both methods indicate that Fe, Ni, O, Si, and S are the most abundant elements in the Sun. These elements are produced in the deep interior of supernovae.
O. Manuel et al., "The Oxygen to Carbon Ratio in the Solar Interior: Information from Nuclear Reaction Cross-Sections," Journal of Fusion Energy, vol. 23, pp. 55-62, Springer Verlag, Mar 2004.
The definitive version is available at http://dx.doi.org/10.1007/s10894-004-1872-4
Foundation for Chemical Research
University of Missouri--Rolla
Keywords and Phrases
Astrophysics; Carbon; Combustion; Fractionation; Helium; Iron; Isotopes; Nickel; Oxygen; Sun; Composition of the Sun; Helium-Burning; S-Products in the Sun; Solar O/C Ratio; Fusion Reactions; Composition of the Sun; Helium-Burning; S-Products in the Sun; Solar O/C Ratio
International Standard Serial Number (ISSN)
Article - Journal
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