تقرير
A grid of MARCS model atmospheres for S stars
| العنوان: | A grid of MARCS model atmospheres for S stars |
|---|---|
| المؤلفون: | Van Eck, Sophie, Neyskens, Pieter, Plez, Bertrand, Jorissen, Alain, Edvardsson, Bengt, Eriksson, Kjell, Gustafsson, Bengt, Jorgensen, Uffe-Grae, Nordlund, Ake |
| سنة النشر: | 2010 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Solar and Stellar Astrophysics |
| الوصف: | S-type stars are late-type giants whose atmosphere is enriched in carbon and s-process elements because of either extrinsic pollution by a binary companion or intrinsic nucleosynthesis and dredge-up on the thermally-pulsing AGB. A large grid of S-star model atmospheres has been computed covering the range 2700 < Teff < 4000 K with 0.5 < C/O < 0.99. ZrO and TiO band strength indices as well as VJHKL photometry are needed to disentangle Teff, C/O and [s/Fe]. A "best-model finding tool" was developed using a set of well-chosen indices and checked against photometry as well as low- and high-resolution spectroscopy. It is found that applying M-star model atmospheres (i.e., with a solar C/O ratio) to S stars can lead to errors on Teff up to 400K. We constrain the parameter space occupied by S stars of the vast sample of Henize stars in terms of Teff, [C/O] and [s/Fe]. Comment: 5 pages, 4 figures, "Why Galaxies Care About AGB Stars II" Conference, Vienna Aug. 2010, to appear in ASP Conference Series |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/1011.2092 |
| رقم الأكسشن: | edsarx.1011.2092 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |