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We investigate two topics regarding solar mass FGK-type stars, the lithium rotation connection (LRC) and the existence of the lithium desert. We determine the minimum critical rotation velocity ($v sin i$) related with the LRC separating slow from rapid stellar rotators, as being 5 km s$^{-1}$. This value also split different stellar properties. For the first time we explore the behaviour of the LRC for some stellar associations with ages between 45 Myr and 120 Myr. This allows us to study the LRC age dependence at the beginning of the general spin down stage for low mass stars, which starts at $sim$ 30-40 Myr. We find that each stellar group presents a characteristic minimum lithium (Li) depletion connected to a specific large rotation velocity and that this minimum changes with age. For instance, this minimum changes from $sim$ 50 km s$^{-1}$ to less than 20 km s$^{-1}$ in 200 Myr. Regarding the lithium desert, it was described as a limited region in the A(Li)-$T_{rm eff}$ map containing no stars. Using $T_{rm eff}$ from {em Gaia} DR2 we detect 30 stars inside and/or near the same box defined originally as the Li desert. Due to their intrinsic $T_{rm eff}$ errors some of these stars may be inside or outside the box, implying a large probability that the box contains several stars. Considering this last fact the lithium desert appears to be more a statistical distribution fluctuation than a real problem.
The aim of the present study is to determine the Li abundances for a large set of the FGK dwarfs and to analyse the connections between the Li content, stellar parameters, and activity. Atmospheric parameters, rotational velocities and Li abundances
We previously attempted to ascertain why the Li I 6708 line-strengths of Sun-like stars differ so significantly despite the superficial similarities of stellar parameters. We carried out a comprehensive analysis of 118 solar analogs and reported that
Open clusters (OC) of 1-3 Gyr age contain intermediate-to-low-mass stars in evolutionary phases of multiple relevance to understanding Li evolution. Stars leaving the main sequence (MS) from the hot side of the Lithium dip (LD) at a fixed age can inc
Context. The abundance inhomogeneities of light elements observed in Globular Clusters (GCs), and notably the ubiquitous Na-O anti-correlation, are generally interpreted as evidence that GCs comprise several generations of stars. There is an on-going
The evolution of lithium abundance over a stars lifetime is indicative of transport processes operating in the stellar interior. We revisit the relationship between lithium content and rotation rate previously reported for cool dwarfs in the Pleiades