Poster abstract

Emergence of a magnetic flux tube through the chromosphere
T.D. Arber, G.J.J. Botha, C.S. Brady


We present 3D numerical simulations of a magnetic flux tube emerging from the upper layers of the convection zone, through the photosphere and chromosphere into the corona. Parts of the solar atmosphere are at sufficiently low temperatures to be partially ionized, particularly the photosphere and lower chromosphere. It is known that ion-neutral collisions add an effective anisotropic resistivity into the single-fluid MHD equations. Moving from a fully to partially ionized gas also changes the density and pressure profiles by orders of magnitude. We prescribe a temperature profile and calculate the density and pressure from this. Then we allow a flux tube to emerge through the atmospheric layers and show how the partial ionizations influence this emergence when compared to emergence in a fully ionised atmosphere.