Carbon Stars and Nucleosynthesis in Galaxies
نویسندگان
چکیده
The role of carbon stars in the build-up of chemical elements in galaxies is discussed on the basis of stellar evolution calculations and estimated stellar yields, abundance analyses of AGB stars, galactic-evolution models and abundance trends among solar-type disk stars. We conclude that the AGB stars in general, and carbon stars in particular, probably are main contributors of s-elements, that their contributions of ourine and carbon are quite signi cant, and that possibly their contributions of lithium, C and Ne are of some importance. Also contributions of N, Na and Al are discussed. The major uncertainties that characterize almost any statement concerning these issues are underlined.
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