CORONAL LOOP FORMATION RESULTING FROM PHOTOSPHERIC CONVECTION

We have demonstrated the dynamic formation of coronal magnetic loops in three dimensions as a result of horizontal vortex-like convection on the photosphere. Localized plasma motions twist the bipolar magnetic field lines which are tied to the dense photosphere by high electrical conductivity. The twists propagate into the corona along the field and create a narrow quasi-toroidal region where the field lines interwind. At the same time, this tubelike region rises in altitude, expands in cross section, and distorts into a slight S shape before settling into an equilibrium state. The MHD stability of such line-tied magnetic loop structures is directly exhibited by this dynamic simulation.