Vertical shear mixing in stellar radiative zones

Abstract

Jean-Paul Zahn’s formalism for vertical shear mixing is used in several stellar evolution codes, but the physics of the shear instability in stellar radiative zones is still not completely understood. Over the last few years, numerical simulations have provided new constraints on the shear instability, including the effect of thermal diffusion and chemical stratification. We present here new simulations that show the effect of viscosity on the vertical turbulent transport due to the shear instability.