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Detailed Analysis of Nearby Bulgelike Dwarf Stars II. Lithium Abundances

Luciana Pompeia·Beatriz Barbuy·Michel Grenon·Bruno Castilho
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Abstract

Li abundances are derived for a sample of bulgelike stars with isochronal ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as small as 2-3 kpc and Zmax < 1 kpc. The sample comprises G and K dwarf stars in the metallicity range -0.80<[Fe/H]< +0.40. Few data of Li abundances in old turn-off stars (> 4.5 Gyr) within the present metallicity range are available. M67 (4.7 Gyr) and NGC 188 (6 Gyr) are the oldest studied metal-rich open clusters with late-type stars. Li abundances have also been studied for few samples of old metal-rich field stars. In the present work a high dispersion in Li abundances is found for bulgelike stars for all the metallicity range, comparable with values in M67. The role of metallicity and age on a Li depletion pattern is discussed. The possible connection between Li depletion and oxygen abundance due to atmospheric opacity effects is investigated.

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Luciana Pompeia, Beatriz Barbuy, Michel Grenon, Bruno Castilho. 2002-01-29. Detailed Analysis of Nearby Bulgelike Dwarf Stars II. Lithium Abundances. https://doi.org/10.1086/339742

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