{
  "id": "1011.2054",
  "version": "v1",
  "published": "2010-11-09T12:03:22.000Z",
  "updated": "2010-11-09T12:03:22.000Z",
  "title": "Abundance Patterns in S-type AGB stars : Setting Constraints on Nucleosynthesis and Stellar Evolution Models",
  "authors": [
    "Pieter Neyskens",
    "Sophie Van Eck",
    "Bertrand Plez",
    "Stéphane Goriely",
    "Lionel Siess",
    "Alain Jorissen"
  ],
  "comment": "5 pages, 3 figures, To be published in the proceedings of the conference \"Why Galaxies Care about AGB Stars II\", held in Vienna, August 16-20, 2010; eds Franz Kerschbaum, Thomas Lebzelter, and Bob Wing, ASP Conf. Series",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "During the evolution on the AGB, S-type stars are the first objects to experience s-process nucleosynthesis and third dredge-ups, and therefore to exhibit sprocess signatures in their atmospheres. Their significant mass loss rates (10^-7 to 10^-6 M*/year) make them major contributors to the AGB nucleosynthesis yields at solar metallicity. Precise abundance determinations in S stars are of the utmost importance for constraining e.g. the third dredge-up luminosity and efficiency (which has been only crudely parameterized in all current nucleosynthetic models so far). Here, dedicated S-star model atmospheres are used to determine precise abundances of key s-process elements, and to set constraints on nucleosynthesis and stellar evolution models. A special interest is paid to technetium, an element with no stable isotopes (99Tc, the only isotope produced by the s-process in AGB stars, has a half-life of 2.1 x 10^5 years). Its detection is considered as the best signature that the star effectively populates the thermally-pulsing AGB phase of evolution. The derived Tc/Zr abundances are compared, as a function of the derived [Zr/Fe] overabundances, with AGB stellar model predictions. The [Zr/Fe] overabundances are in good agreement with the model predictions, while the Tc/Zr abundances are slightly overpredicted. This discrepancy can help to set better constraints on nucleosynthesis and stellar evolution models of AGB stars.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2010-11-09T12:03:22.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "stellar evolution models",
      "s-type agb stars",
      "abundance patterns",
      "nucleosynthesis",
      "setting constraints"
    ],
    "tags": [
      "conference paper"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 876567,
      "adsabs": "2011ASPC..445...77N"
    }
  }
}