Precise Li abundances in metal-poor stars: depletion in the Spite plateau

• Type: Article in International Conference Proceedings Book
• Date: 2010

Authors

J. Melendez (Author) FCUP; L. Casagrande (Author) FCUP; I. Ramirez (Author) FCUP; M. Asplund (Author) FCUP

Conference proceedings International

Title: CHEMICAL ABUNDANCES IN THE UNIVERSE: CONNECTING FIRST STARS TO PLANETS

Pages: 71-72

265th Symposium of the International-Astronomical-Union

Rio de Janeiro, 10 a 14 de Agosto de 2009

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ISI Web of Science

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Abstract (EN): We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM. temperatures (Casagrande at al. 2009) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality equivalent widths (sigma(EW) similar to 3. At all metallicities we uncover a fine-structure in the Li abundances of Spite plateau stars, which we trace to Li depletion that depends on both metallicity and mass. Models including atomic diffusion and turbulent mixing seem to reproduce the observed Li depletion assuming a primordial Li abundance A(Li) = 2.64 dex (MARES models) or 2.72 (Kurucz overshooting models), in good agreement with current predictions (A(Li) = 2.72) from standard BBV.

Language: English

Type (Professor's evaluation): Scientific