Magnetic Structure of Twin Filaments Inside Pseudostreamers

Among the large scale coronal structures, pseudostreamers appear in unipolar regions above multiple polarity reversal boundaries. Some of these polarity reversal boundaries can be filament channels, and when this is the case they always occur as twin filament channels often containing twin filaments. The magnetic structure of pseudostreamers with and without twin filaments lying at their base is significantly different. Branches of pseudostreamers on opposite sides of the separatrix surface diverge when filaments are present. Here we analyze possible current and magnetic field configurations of the complete pseudostreamer system and study the links between its separate parts, which include open field lines of pseudostreamers, filament channels, filaments, cavities, overlying filament arcades. The presence of well developed filaments of the same chirality at the base of pseudostreamers implies the presence of a vertical current sheet, which divides and repeal branches of the pseudostreamer field lines in 3D. We discuss the 3D magnetic topology of the filament, filament cavity and overlying filament arcades for these twin systems and its implications on the theories for filaments an filament eruptions.