Chemical abundances of the metal-poor horizontal-branch stars CS 22186-005 and CS 30344-033

  title={Chemical abundances of the metal-poor horizontal-branch stars CS 22186-005 and CS 30344-033},
  author={Şeyma Çalışkan and Elisabetta Caffau and Piercarlo Bonifacio and Norbert Christlieb and Lorenzo Monaco and Timothy C. Beers and Berahitdin Albayrak and Luca Sbordone},
  journal={Astronomy and Astrophysics},
We report on a chemical-abundance analysis of two very metal-poor horizontal-branch stars in the Milky Way halo: CS 22186-005 ((Fe/H) = −2.70) and CS 30344-033 ((Fe/H) = −2.90). The analysis is based on high-resolution spectra obtained at ESO, with the spectrographs HARPS at the 3.6 m telescope, and UVES at the VLT. We adopted one-dimensional, plane-parallel model atmospheres assuming local thermodynamic equilibrium. We derived elemental abundances for 13 elements for CS 22186-005 and 14… 
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