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AGB and Post-AGB Evolution: Structural and Chemical Changes

T. Bloecker·R. Osterbart·G. Weigelt·Y. Balega·A. Men'shchikov
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Abstract

Structural and chemical changes during the AGB and post-AGB evolution are discussed with respect to two recent observational and theoretical findings. On the one hand, high-resolution infrared observations revealed details of the dynamical evolution of the fragmented, bipolar dust shell around the far-evolved carbon star IRC+10216 giving evidence for rapid changes of an already PPN-like structure during the very end of the AGB evolution. On the other hand, stellar evolution calculations considering convective overshoot have shown how thermal pulses during the post-AGB stage lead to the formation of hydrogen-deficient post-AGB stars with abundance patterns consistent with those observed for Wolf-Rayet central stars.

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T. Bloecker, R. Osterbart, G. Weigelt, Y. Balega, A. Men'shchikov. 2001-02-22. AGB and Post-AGB Evolution: Structural and Chemical Changes. https://doi.org/10.1007/978-94-015-9688-6_37

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