The behaviour of Li abundance in the stars of different metallicities

Abstract

Using the method of spectral synthesis we derived the abundances of Li in the atmospheres of 100 stars in the range of metallicities −3${<}$[Fe/H]${<}$0.2. The investigated spectra are part of the library collected at the Haute Provence Observatory, they were obtained with the 193 cm telescope equipped with ELODIE spectrometer (R=42000). For the metal-poor dwarfs, in the “Spite plateau” region ([Fe/H]${<}$−1.7, $T_{\rm {eff}}{>}$5700 K) we obtain logA(Li)${=}$2.30${\pm}$0.05, which is in a good agreement with the results of other authors. Our values of Li abundances do not indicate any trends either with $T_{\rm {eff}}$ or with [Fe/H]. The “plateau” is also traced in the metallicity range −0.7${<}$[Fe/H]${<}$−0.3. The behavior of the lithium abundance for stars with [Fe/H]${>}$−1.7, $T_{\rm {eff}}{<}$5700 K shows a depleting mechanism in these stars, the growth of its efficiency with an increase of the metallicity. The “lithium plateau” was also found for thick disk dwarfs with $T_{\rm {eff}}{>}$5800 K.