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The origin of carbon, investigated by spectral analysis of solar-type stars in the Galactic Disk

B. Gustafsson·T. Karlsson·E. Olsson·B. Edvardsson·N. Ryde
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Abstract

Abundance analysis of carbon has been performed in a sample of 80 late F and early G type dwarf stars in the metallicity range -1.06 < [Fe/H] < 0.26 using the forbidden [C I] line at 8727 A. This line is presumably less sensitive to temperature, atmospheric structure and departures from LTE than alternative carbon criteria. We find that [C/Fe] decreases slowly with increasing [Fe/H] with an overall slope of -0.17 +- 0.03. Our results are consistent with carbon enrichment by superwinds of metal-rich massive stars but inconsistent with a main origin of carbon in low-mass stars. This follows in particular from a comparison between the relation of [C/O] with metallicity for the Galactic stars and the corresponding relation observed for dwarf irregular galaxies. The significance of intermediate-mass stars for the production of carbon in the Galaxy is still somewhat unclear.

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B. Gustafsson, T. Karlsson, E. Olsson, B. Edvardsson, N. Ryde. 1998-11-20. The origin of carbon, investigated by spectral analysis of solar-type stars in the Galactic Disk. https://arxiv.org/abs/astro-ph/9811303

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