The Chemical Compositions of the Extreme Halo Stars HE 0107–5240 and HE 1327–2326 Inferred from Three-dimensional Hydrodynamical Model Atmospheres

  title={The Chemical Compositions of the Extreme Halo Stars HE 0107–5240 and HE 1327–2326 Inferred from Three-dimensional Hydrodynamical Model Atmospheres},
  author={Remo Collet and Martin Asplund and Regner Trampedach},
  journal={The Astrophysical Journal Letters},
  pages={L121 - L124}
We investigate the impact of realistic three-dimensional (3D) hydrodynamical model stellar atmospheres on the determination of elemental abundances in the carbon-rich, hyper-iron-poor stars HE 0107-5240 and HE 1327-2326. We derive the chemical compositions of the two stars by means of a detailed 3D analysis of spectral lines under the assumption of local thermodynamic equilibrium (LTE). The lower temperatures of the line-forming regions of the hydrodynamical models cause changes in the… 

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