(Pre)-white dwarf stars as measuring tools for yields of AGB nucleosynthesis. Issue Volume 15:Issue S357(2019) (October 2019)

• Record Type: Journal Article
• Authors: Löbling, Lisa
• Editors: Barstow, Martin A.; Kleinman, Scot J.; Provencal, Judith L.; Ferrario, Lilia
• Is Part Of: Proceedings of the International Astronomical Union. Volume 15:Issue S357(2019)
• Page Start: 158
• Page End: 161
• Publication Date: 2019-10
• Subjects: atomic data, -- techniques: spectroscopic, -- stars: abundances, -- stars: AGB and post-AGB, -- stars: atmospheres, -- white dwarfs, -- planetary nebulae; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921320000617
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: In the helium-rich intershell region of asymptotic giant branch (AGB) stars, slow neutron-capture nucleosynthesis produces heavy elements beyond iron. If the stars experience a final-flash of the He-burning shell, a pulse-driven convection zone establishes, the stars become hydrogen-deficient and exhibit former intershell material at their surfaces. In their subsequent evolution towards the white-dwarf cooling sequence, but still at constant luminosity, a strong stellar wind prevents diffusion to wipe out the information about AGB yields. We present and interpret the analysis results of hydrogen-rich and -deficient post-AGB stars, discuss difficulties in their analysis and review the implications on the understanding of post-AGB evolution.