We report new abundances of Rb and Zr in a sample of massive Galactic asymptotic giant branch (AGB) stars that were previously studied with hydrostatic models by using more realistic dynamical model atmospheres. We use a modified version of the spectral synthesis code Turbospectrum, and consider the presence of a circumstellar envelope and a radial wind in the modelling of these Galactic AGB stars. The Rb and Zr are determined from the 7800 Å Rb I resonant line and the 6474 Å ZrO bandhead, respectively, and they are compared with the AGB nucleosynthesis theoretical predictions. The derived Rb abundances are much lower (∼1-2 dex) with the new dynamical models, while the Zr abundances, however, are closer to the hydrostatic values. The new model atmospheres can help to resolve the problem of the mismatch between the observations and the nucleosynthesis theoretical predictions of massive AGB stars.
|Number of pages
|Published - 8 Aug 2016
|Pacific Rim Stellar Conference on Stellar Astrophysics 2015: Physics and Chemistry of the Late Stages of Stellar Evolution - The University of Hong Kong (HKU), Hong Kong, China
Duration: 14 Dec 2015 → 17 Dec 2015
Conference number: 11
|Pacific Rim Stellar Conference on Stellar Astrophysics 2015
|14/12/15 → 17/12/15