Realistic Numerical Modeling of Solar Magnetoconvection and Oscillations (0901.4369v2)

Abstract: We have developed 3D, compressible, non-linear radiative MHD simulations to study the influence of the magnetic field of various strength and geometry on the turbulent convective cells and on the excitation mechanisms of the acoustic oscillations. The results reveal substantial changes of the granulation structure with increased magnetic field, and a frequency-dependent reduction in the oscillation power. These simulation results reproduce the enhanced high-frequency acoustic emission observed at the boundaries of active region ("acoustic halo" phenomenon). In the presence of inclined magnetic field the solar convection develops filamentary structure with flows concentrated along magnetic filaments, and also exhibits behavior of running magnetoconvective waves, resembling recent observations of the sunspot penumbra dynamics from Hinode/SOT.