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Mapping Stellar Evolution and Nucleosynthesis in Asymptotic Giant Branch Stars via High-Resolution Spectroscopy Verne V. Smith Abstract During the evolution of low and intermediate mass stars along the asymptotic giant branch (AGB), a rich variety of nuclear processes can produce profound changes in the interior abundances of many elements, such as lithium, carbon, nitrogen, oxygen, sodium, magnesium, or aluminum, as well as the heavier slow-neutron-capture (the s-process) elements. These abundance changes can be observed both in individual AGB stars, due to deep mixing, or in some stellar populations, where previous generations of AGB stars have left their signatures in the chemical evolutionary patterns now observed in present stars or gas. Various observed abundance patterns, and what they tell us about the interiors of AGB stars, will be reviewed. |