High-resolution spectroscopic observations of two s-process-enriched and carbon-poor post-AGB stars: GLMP 334 and IRAS 15482-5741

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Stars: Agb And Post-Agb, Stars: Evolution, Stars: Abundances, Stars: Chemically Peculiar

Scientific paper

Aims: The study of post-AGB stars provides important information on the s-process inside asymptotic giant branch (AGB) stars. We determined the atmospheric parameters and abundance patterns of two post-AGB stars: GLMP 334 and IRAS 15482-5741 to better understand their evolutionary state and the nature of the s-element enhancement of these stars. Methods: We used high-resolution optical spectroscopy. Atmospheric parameters and abundances were determined in the local-thermodynamic-equilibrium model atmospheres of Kurucz (1993, CD-ROM 13, SAO) using the spectral analysis code MOOG. Spectroscopic observations are compared with nucleosynthesis AGB models of different initial masses and s-process efficiencies. Results: Theoretical interpretations are presented and discussed. The observed distribution of neutron capture elements can be fitted with particular choices of AGB initial masses and of the 13C neutron source (13C-pocket strengths) obtained at the adopted [Fe/H] for each star, but the low [C/Fe] observed is incompatible with model predictions. The problem can be solved by increasing the metallicity by 0.2 dex, which is inside the spectroscopic uncertainty. The abundances of carbon and nitrogen observed in these stars may support the occurrence of an extra-mixing episode, the "cool bottom process", even if its exact effect cannot be theoretically quantified yet.
Based on observations made with the 2.2 m telescope at the European Southern Observatory (La Silla, Chile).Tables 2, 4 and Appendix A are available in electronic form at http://www.aanda.org

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

High-resolution spectroscopic observations of two s-process-enriched and carbon-poor post-AGB stars: GLMP 334 and IRAS 15482-5741 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with High-resolution spectroscopic observations of two s-process-enriched and carbon-poor post-AGB stars: GLMP 334 and IRAS 15482-5741, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High-resolution spectroscopic observations of two s-process-enriched and carbon-poor post-AGB stars: GLMP 334 and IRAS 15482-5741 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-887344

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.