Micro- and macroturbulence derived from 3D hydrodynamical stellar atmospheres
Abstract
The theoretical prediction of micro- and macroturbulence (ximic and ximac) as a function of stellar parameters can be useful for spectroscopic work based on 1D model atmospheres in cases where an empirical determination of ximic is impossible due to a lack of suitable lines and/or macroturbulence and rotational line broadening are difficult to separate. In an effort to exploit the CIFIST 3D model atmosphere grid for deriving the theoretical dependence of ximic and ximac on effective temperature, gravity, and metallicity, we discuss different methods to derive ximic from the numerical simulations, and report first results for the Sun and Procyon. In both cases the preliminary analysis indicates that the microturbulence found in the simulations is significantly lower than in the real stellar atmospheres.