PHOTOSPHERIC MOTIONS AND THEIR EFFECTS ON THE CORONA: A NUMERICAL APPROACH

We perform a number of numerical simulations of the solar corona with the aim of understanding how it responds to different conditions in the photosphere. By changing parameters which govern the motion of the plasma at the photosphere, we study the behavior of the corona, in particular, the effects on the current density generated. A magnetohydrodynamics code is used to run simulations, using a 20 x 20 x 20 Mm3 box with timespans ranging from one hundred to several hundreds of minutes. All the experiments show a fast initial increase of the current density, followed by a stabilization around an asymptotic value which depends on the photospheric conditions. These asymptotic average current densities as well as the turnover points are discussed.