Lithium depletion and angular momentum transport in F-type and G-type
  stars in Galactic open clusters
  Open clusters provide clues to understand the evolution of Li7 at the surface
of low-mass stars and its possible correlation with stellar rotation, which is
a challenge for both stellar hydrodynamics and Galactic chemical evolution. We
aim to quantify the efficiency of the transport processes for both angular
momentum and chemicals that are required to explain simultaneously the observed
behaviour of surface Li7 and rotation as well as the internal rotation profiles
inferred from helio- and asteroseismology in F- and G-type main sequence stars.
We apply the model for the transport of angular momentum and chemicals that we
tailored in a previous work for solar-type stars to an extended range of
initial masses and metallicities corresponding to F- an G-type stars in a
sample of 20 Galactic open clusters. We evaluate its ability to explain the
Li7, Be9, and rotation periods observations. Over the entire range of masses,
metallicities, and ages explored, we reproduce the evolution of the surface
rotation rates and predict, for the first time, the observed anti-correlation
between the surface rotation rate and Li7 depletion as a consequence of the
penetrative convection prescription. However, the ability of the model to
reproduce the so-called Li7 dip centred around 6600K strongly depends on the
adopted prescriptions for shear turbulence. It also requires a stellar mass
dependence for the viscosity adopted for the transport of angular momentum,
similar to the behaviour predicted for the generation and luminosity of
internal gravity waves generated by stellar convective envelopes. We provide an
efficient way to model G-type stars of different ages and metallicities
successfully. However, the Li7 and Be9 dip constraints call for further
hydrodynamical studies to better model turbulence in stars.
