Turbulent Dynamics of Main-Sequence Stars with Shallow Outer Convection Zones Revealed in 3D Radiative Hydrodynamics Simulations

Modeling of stars, more massive than the Sun, with shallow convection zones opens an opportunity to investigate their turbulent dynamics in great detail, from non-linear self-organization of multiscale convection patterns to mechanisms of acoustic wave excitation near the photosphere and interface between the radiative and convection zones, as well as excitation of the internal gravity waves. We perform 3D radiative hydrodynamics simulations using the StellarBox code to model moderate-mass stars of different masses and metallicity and analyze the simulation results to study the coupling of rotation, convection, and stellar oscillations. Each stellar model includes the upper radiative zone, the whole convection zone, and the lower atmosphere. This allows us to investigate how properties of the convection zone structure and dynamics depend on the global properties of stars, such as the stellar mass and metallicity. In addition, we discuss mechanisms and properties of acoustic and internal gravity waves excited near the photosphere by turbulent high-speed downdrafts (~20km/s) and the convective overshoot layer at the bottom of the convection zone. This work is supported by NASA Astrophysical Theory Program.