Tomographic imaging of the polar-cap ionosphere over Svalbard

First results are presented from an experiment to image the electron density in the polar-cap ionosphere above Svalbard using tomographic techniques. The results show localised enhanced densities in the cusp and throat region, the elevated densities of a polar patch, relatively low densities in corotating plasma flux tubes in darkness at lower latitudes and the depleted densities of the polar hole. The reconstruction of these features, known to occur at polar latitudes, confirms the potential of tomography for imaging the ionosphere at these very high latitudes.