Poster abstract

3D simulation of flux emergence from convective zone with SWMF
Fang Fang, Chip Ward Manchester, William P Abbett, Bart van der Holst


To study the interaction between magnetic field and convective motion, we present a 3d simulation of the emergence of magnetic flux ropes from the convective zone into the corona, applying radiation terms and non-ideal equation of state table to BATSRUS code. To perform this simulation, we first generate a solar atmosphere, whose physical properties are comparable with Bercik(2002) data, with a turbulent convective zone. The upgoing convective motion is cooled down and stopped by the surface loss and sharp temperature decrease at photosphere. The magnetic flux is observed to concentrate at the intergranular lanes with downflowing plasma and decrease in the granules. We then heat up the corona to temperature of above 1MK, using an empirical relationship between heating and unsigned magnetic flux. In the high-temperature, low-density upper atmosphere, radiative loss term is approximated with optically thin limit and the radiative cooling curve is obtained from CHIANTI database. The Field aligned heat conduction is applied to channel heat flux along the magnetic field lines in corona and form a more realistic transition region. After producing a superadiabatic atmosphere matching the observed properties, we introduce a buoyant magnetic flux rope below the photosphere. The flux rope shows shear flow with velocity of 8km/s at the photosphere where it emerges. We then compare our results with previous simulations without convection (Manchester et al. 2004).