English

AGB and SAGB stars: modelling dust production at solar metallicity

Solar and Stellar Astrophysics 2017-07-26 v1

Abstract

We present dust yields for asymptotic giant branch (AGB) and super--asymptotic giant branch (SAGB) stars of solar metallicity. Stars with initial mass 1.5 MMini3 M1.5~M_{\odot} \leq M_{\rm ini} \leq 3~M_{\odot} reach the carbon star stage during the AGB phase and produce mainly solid carbon and SiC. The size and the amount of the carbon particles formed follows a positive trend with themass of the star; the carbon grains with the largest size (aC0.2μa_{\rm C} \sim 0.2\mum) are produced by AGB stars with Mini=2.53 MM_{\rm ini} = 2.5-3~M_{\odot}, as these stars are those achieving the largest enrichment of carbon in the surface regions. The size of SiC grains, being sensitive to the surface silicon abundance, keeps around aSiC0.1μa_{\rm SiC} \sim 0.1\mum. The mass of carbonaceous dust formed is in the range 1045×103 M10^{-4} - 5\times 10^{-3}~M_{\odot}, whereas the amount of SiC produced is 2×104103 M2\times 10^{-4} - 10^{-3}~M_{\odot}. Massive AGB/SAGB stars with Mini>3 MM_{\rm ini} > 3~M_{\odot} experience HBB, that inhibits formation of carbon stars. The most relevant dust species formed in these stars are silicates and alumina dust, with grain sizes in the range 0.1μm<aol<0.15μ0.1\mu m < a_{\rm ol} < 0.15\mum and aAl2O30.07μa_{\rm Al_2O_3} \sim 0.07\mum, respectively. The mass of silicates produced spans the interval 3.4×103 MMdust1.1×102 M3.4\times 10^{-3}~M_{\odot} \leq M_{\rm dust} \leq 1.1\times 10^{-2}~M_{\odot} and increases with the initial mass of the star.

Keywords

Cite

@article{arxiv.1702.03904,
  title  = {AGB and SAGB stars: modelling dust production at solar metallicity},
  author = {F. Dell'Agli and D. A. García-Hernádez and R. Schneider and P. Ventura and F. La Franca and R. Valiante and E. Marini and M. Di Criscienzo},
  journal= {arXiv preprint arXiv:1702.03904},
  year   = {2017}
}

Comments

Accepted for publication in MNRAS