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We present a survey of lithium abundances in 185 main- sequence field stars with Teff between 5600 and 6600 K and [Fe/H] from -1.4 to +0.2 based on high-resolution spectra of 130 stars and a reanalysis of data from Lambert et al. (1991). The survey takes advantage of improved ways of determining effective temperature, metallicity, mass and age, offering an opportunity to investigate the behaviour of Li as a function of these parameters. An interesting result is the presence of a large gap in the Li-Teff plane, which distinguishes `Hyades-like, Li-dip stars from other stars. These Li-dip stars have a well-defined mass, which decreases with metallicity. Stars above the gap, when divided into four metallicity groups, may show a correlation between Li abundance and stellar mass, but with a large dispersion that cannot be explained by observational errors or differences in metallicity and age, which ranges from 1.5 to 15 Gyr. This suggests that Li depletion occurs early in stellar life and that other parameters, e.g. initial rotation velocity and/or the rate of angular momentum loss, affect the degree of depletion. A comparison of the distribution of stars in the Li-[Fe/H] plane with evolutionary models of Romano et al. (1999) suggests that novae are a major source for the Li production in the Galactic disk.
The application to main-sequence stars of the rotation-induced mixing theory in the presence of mu-gradients leads to partial mixing in the lithium destruction region, not visible in the atmosphere. The induced lithium depletion becomes visible in th
Aims: We study the influence of rotation and disc lifetime on lithium depletion of pre-main sequence (PMS) solar-type stars. Methods: The impact of rotational mixing and of the hydrostatic effects of rotation on lithium abundances are investigated by
We estimate cluster ages from lithium depletion in five pre-main-sequence groups found within 100 pc of the Sun: TW Hydrae Association, Eta Chamaeleontis Cluster, Beta Pictoris Moving Group, Tucanae-Horologium Association and AB Doradus Moving Group.
We have used fibre spectroscopy to establish cluster membership and examine pre-main-sequence (PMS) lithium depletion for low-mass stars (spectral types F to M) in the sparse young (~30 Myr) cluster IC 4665. We present a filtered candidate list of 40
In this paper we study the evolution of 7Li in the Galaxy considering the contributions of various stellar sources: type II supernovae, novae, red giant stars, and asymptotic giant branch (AGB) stars. We present new results for the production of 7Li