Two-dimensional imaging of plasma density structures in auroral ionosphere

Abstract

We present multi-instrumental observation of auroral ionosphere by using the EISCAT UHF radar, all sky imager, GNSS satellites and Synthetic Aperture Radar (SAR) satellite. Plasma irregularities generated by auroral precipitating particles are imaged by SAR phase data in high resolution (less than kilometer) in the two dimensional form over the area of several tens of kilometers. The observed localized density irregularities are aligned in east-west direction near the location of 558-nm optical emission. The results suggest that highly structured plasma density gradients exist primarily near the edge of the precipitation region. The level of density enhancement is approximately 5 TECU (Total Electron Content Unit) from a GNSS receiver collocated at the UHF radar. We show that L-band satellite data provides complemental observation for the current and future EISCAT/EISCAT3D facilities to study high-latitude ionosphere in multi-scale.