Gyroscopic pumping of large-scale flows in stellar interiors, and application to Lithium Dip stars

摘要: The maintenance of large-scale differential rotation in stellar convective regions by rotationally influenced stresses also drives meridional flows angular--momentum conservation. This process is an example ``gyroscopic pumping'', and has recently been studied detail the solar context. An important question concerns extent to which these gyroscopically pumped penetrate into nearby stably stratified (radiative) regions, since they could potentially be source non-local mixing. Here we present extensive study gyroscopic pumping mechanism, using a combination analytical calculations numerical simulations both Cartesian geometry spherical geometry. various methods, when compared with one another, provide physical insight itself, as well increasingly sophisticated means estimating rate. As application, investigate effects this mixing on surface abundances light elements Li Be for stars mass range 1.3-1.5 masses (so-called ``Li-dip stars''). We find that very efficient mechanism circulating material between deep interior, so much fact it over-estimates depletion orders magnitude hot side dip.However, diffusion chemical species back convection zone taken account, good fit observed function Hyades cluster can found reasonable choices model parameters.