First stars IX- mixing in extremely metal-poor giants. Variation of the 12C/13C, [Na/Mg] and [Al/Mg] ratios

@article{Spite2006FirstSI,
  title={First stars IX- mixing in extremely metal-poor giants. Variation of the 12C/13C, [Na/Mg] and [Al/Mg] ratios},
  author={Monique Spite and Roger. Cayrel and Vanessa Hill and Franccois Spite and P. François and Bertrand Plez and Piercarlo Bonifacio and Paolo Molaro and {\'E}ric Depagne and Johannes Andersen and Beatriz Barbuy and Timothy C. Beers and B. Nordstroem and Francesca Primas},
  journal={Astronomy and Astrophysics},
  year={2006},
  volume={455},
  pages={291-301}
}
Context: .Extremely metal-poor (EMP) stars preserve a fossil record of the composition of the ISM when the Galaxy formed. It is crucial, however, to verify whether internal mixing has modified their surface composition, especially in the giants where most elements can be studied. Aims: .We aim to understand the CNO abundance variations found in some, but not all EMP field giants analysed earlier. Mixing beyond the first dredge-up of standard models is required, and its origin needs… 
First stars - XIII. Two extremely metal-poor RR Lyrae stars
Context. The chemical composition of extremely metal-poor stars (EMP stars; [Fe/H] < ∼− 3) is a unique tracer of early nucleosynthesis in the Galaxy. As such stars are rare, we wish to find classes
High-resolution Spectroscopy of Extremely Metal-poor Stars from SDSS/SEGUE. III. Unevolved Stars with [Fe/H] ≲ −3.5
We present elemental abundances for eight unevolved extremely metal-poor stars with Teff > 5500K, among which seven have [Fe/H] < −3.5. The sample is selected from the Sloan Digital Sky Survey /
NORMAL AND OUTLYING POPULATIONS OF THE MILKY WAY STELLAR HALO AT [Fe/H] <–2*
From detailed abundance analysis of >100 Hamburg/ESO candidate extremely metal-poor (EMP) stars we find 45 with [Fe/H] < –3.0 dex. We identify a heretofore unidentified group: Ca-deficient stars with
First stars X. The nature of three unevolved Carbon-Enhanced Metal-Poor stars ⋆
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Abundances in the most metal-poor stars: nucleosynthesis in the early Milky Way
The detailed abundance patterns in extremely metal-poor (EMP) stars are examined, using the results of the First Stars ESO-VLT Large Program on large samples of dwarfs (located close to the main
The formation of the Milky Way halo and its dwarf satellites; a NLTE-1D abundance analysis. II. Early chemical enrichment
We present the non-local thermodynamic equilibrium (NLTE) abundances of up to 10 chemical species in a sample of 59 very metal-poor (VMP, -4 < [Fe/H] < -2) stars in seven dwarf spheroidal galaxies
First stars XII. Abundances in extremely metal-poor turnoff stars,and comparison with the giants
Context. The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data, however, treat giant
Are C-rich ultra iron-poor stars also He-rich?
Context. The three most iron-poor stars presently known ([Fe/H] equal to –5.96, –5.4 and –4.75) are carbon-rich, so they are called C-Rich Ultra-Metal Poor Stars (CRUMPS). The origin of their
New Extremely Metal-Poor Stars in the Galactic Halo*
We present a detailed abundance analysis based on high-resolution and high signal-to-noise spectra of eight extremely metal-poor (EMP) stars with [ Fe/H ] ≾ − 3.5 dex, four of which are new. Only
Observational Constraints on First-Star Nucleosynthesis. II. Spectroscopy of an Ultra Metal-Poor CEMP-no Star
We report on the first high-resolution spectroscopic analysis of HE0020-1741, a bright (V=12.9), ultra metal-poor ([Fe/H] = -4.1), carbon-enhanced ([C/Fe] = +1.7) star selected from the Hamburg/ESO
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