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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 in AGB stars via the hot bottom burning process, based on stellar evolutionary models by Frost (1997). In the light of recent observations of dense circumstellar shells around evolved stars in the Galaxy and in the Magellanic Clouds, we also consider the impact of a very high mass-loss rate episode (superwind) before the evolution off the AGB phase on the 7Li enrichment in the interstellar medium. We compare the Galactic evolution of 7Li obtained with these new 7Li yields (complemented with a critical re-analysis of the role of supernovae, novae and giant stars) with a selected compilation of spectroscopic observations including halo and disk field stars as well as young stellar clusters. We conclude that even allowing for the large uncertainties in the theoretical calculation of mass-loss rates at the end of the AGB phase, the superwind phase has a significant effect on the 7Li enrichment of the Galaxy.
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 t
Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 {AA} in high-resolution spectra obtained during gravitational microlensing events, when the bright
We used a one-zone chemical evolution model to address the question of how many masses and metallicities are required in grids of massive stellar models in order to ensure reliable galactic chemical evolution predictions. We used a set of yields that
Aims: We aim at measuring mass-loss rates and the luminosities of a statistically large sample of Galactic bulge stars at several galactocentric radii. The sensitivity of previous infrared surveys of the bulge has been rather limited, thus fundamenta
The early science results from the new generation of high-resolution stellar spectroscopic surveys, such as GALAH and the Gaia-ESO survey, will represent major milestones in the quest to chemically tag the Galaxy. Yet this technique to reconstruct di