Drag forces and electric conductivity of the Sq current system in the ionosphere

In this study an analysis of the drag forces, drag conductivity and their relevance to the solar quiet Sq current system in the ionosphere is performed. Particularly, the drag conductivity perpendicular to the static magnetic field is derived and the perpendicular electric current expressed through the drag forces is evaluated quantitatively. The Sq diurnal, seasonal and longitudinal variations may prove to be controlled by i) the perpendicular (drift) current during day hours under high density plasma conditions and ii) by the Pedersen and the Hall currents that practically persist without changes (usually during night hours) under low density plasma conditions. Key words: solar quiet (Sq) current system, plasma-neutrals system, drag forces, drift currents, conductivity