Carbon abundance and the N/C ratio in atmospheres of A-, F- and G-type supergiants and bright giants

  title={Carbon abundance and the N/C ratio in atmospheres of A-, F- and G-type supergiants and bright giants},
  author={L S Lyubimkov and David L. Lambert and Sergey A. Korotin and Tamara M. Rachkovskaya and Dmitry B. Poklad},
  journal={Monthly Notices of the Royal Astronomical Society},
Based on our prior accurate determination of fundamental parameters for 36 Galactic A-, F- and G-type supergiants and bright giants (luminosity classes I and II), we undertook a non-LTE analysis of the carbon abundance in their atmospheres. It is shown that the non-LTE corrections to the C abundances derived from C I lines are negative and increase with the effective temperature Teff; the corrections are especially significant for the infrared C I lines with wavelengths 9060-9660 \AA. The… 
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