A Reappraisal of the Solar Photospheric C/o Ratio

نویسندگان

  • Carlos Allende Prieto
  • David L. Lambert
  • Martin Asplund
چکیده

Accurate determination of photospheric solar abundances requires detailed modeling of the solar granulation and accounting for departures from local thermodynamical equilibrium (LTE). We argue that the forbidden C I line at 8727 Å is largely immune to departures from LTE, and can be realistically modeled using LTE radiative transfer in a time-dependent three-dimensional simulation of solar surface convection. We analyze the [C I] line in the solar flux spectrum to derive the abundance log ǫ(C) = 8.39± 0.04 dex. Combining this result with our parallel analysis of the [O I] 6300 Å line, we find C/O= 0.50±0.07, in agreement with the ratios measured in the solar corona from gamma-ray spectroscopy and solar energetic particles. Subject headings: convection — line: formation — Sun: abundances — Sun: photosphere

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تاریخ انتشار 2002