MHD simulation of electric currents in the solar atmosphere caused by photospheric plasma motion

Abstract

Photospheric plasma motion may cause the build- up of electric currents in the solar atmosphere. These electric currents may then dissipate and heat the corona, cause EUV and X-ray Bright Points (BPs) and trigger flares. In this work we use a 'data driven' 3D MHD model to study the genera- tion of electric currents in the solar atmosphere by photo- spheric plasma motion. The model was applied to photo- spheric measurements below an observed EUV-BP. The ob- served photospheric magnetic field and the derived horizon- tal plasma motion were used as initial and boundary con- ditions of a simulation. The horizontal motion gave rise to electric currents in the chromosphere, transition region and lower corona. The currents formed in the area where the mo- tion was applied and above the main concentrations of the photospheric magnetic field.