Abundance patterns of the light neutron-capture elements in very and extremely metal-poor stars

  title={Abundance patterns of the light neutron-capture elements in very and extremely metal-poor stars},
  author={Franccois Spite and Monique Spite and Beatriz Barbuy and Piercarlo Bonifacio and Elisabetta Caffau and Patrick Franccois},
  journal={Astronomy and Astrophysics},
We measured new abundances of so-called light neutron-capture of first peak elements using local thermodynamic equilibrium (LTE) 1D analysis; this analysis resulted in a sample of 11 very metal-poor stars, from [Fe/H]=-2.5 to [Fe/H]=-3.4, and one carbon-rich star, CS 22949-037 with [Fe/H]=-4.0. The abundances were compared to those observed in two classical metal-poor stars: the typical r-rich star CS 31082-001 ([Eu/Fe] > +1.0) and the r-poor star HD 122563 ([Eu/Fe] < 0.0), which are known to… 
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