Programme by Session

Recent asteroseismological observations of stars with a convective core showed evidence of stochastically excited internal gravity waves (IGWs). IGWs are expected to effectively transport angular momentum and chemical species through the radiative envelope of the star. This has potentially large implications on the evolution of rotating massive stars. We present the first three-dimensional hydrodynamic simulations of the convective core and a large part of the radiative envelope of a main-sequence star. These show the self-consistent convective excitation and propagation of IGWs. The simulations show standing modes consistent with predicted f and g modes. Additionally we see a continuous signal at low frequencies (~30 µHz), which is caused by stochastically excited IGWs. The spectral energy distribution is different from predictions based on theoretical estimates. We compare these synthetic observables to actual photometric observations. We also give an overview on ongoing work on the effect of differential rotation and magnetic fields on IGWs.