[M-GI29] Computational sciences on the universe, galaxies, stars, planets and their environments

[MGI29-02] Sunspot fine structure simulated with large-scale numerical calculation

*Hideyuki Hotta¹ (1.Nagoya University)

Keywords:sunspot, magnetohydrodynamics, thermal convection

We carry out high-resolution numerical simulations for sunspots and partially reproduce the penumbra and the Evershed flows. The outflow from the sunspots was discovered by J. Evershed more than 100 years ago, while we have not understood the origin of the flows in numerical simulation. The inclined magnetic field may be a key to driving the flow, but the current radiative magnetohydrodynamic simulation cannot reproduce it. People use a special top boundary condition to reproduce the inclined magnetic field, but these are inconsistent with the high-resolution observations. We carry out unprecedented high-resolution simulations to resolve the problem. In the highest-resolution simulation, the grid spacing is 3 km. In the simulation, the penumbra and the Evershed flow are partially reproduced. We discuss the origin of these in the talk.