Coordinated EISCAT/DMSP measurements of electron density and energetic electron precipitation

Abstract

A campaign was recently undertaken to obtain simultaneous radar and satellite measurements that would provide insight into the temporal and spatial morphology of the energetic particle precipitation. It included coordinated field‐aligned measurements of the altitudinal profile of the E region electron density from the European Incoherent Scatter (EISCAT) radar, and measurements of the energetic particle precipitation from the SAMPEX and DMSP F10 and F12 satellites. The Strickland auroral electron transport code, with the recent addition of auroral proton transport, was employed to produce density profiles from the energetic particle precipitation measurements by the SSJ/4 sensors on the DMSP F10 and F12 spacecraft for comparison with the EISCAT measurements. We found good agreement between the EISCAT measurements and the model results for three of the four conjunctions including a very close conjunction (< 12 km) when the integral ion energy flux was greater than the integral electron energy flux by a factor of 3 to 4. All of the conjunctions for which the results of the comparison were good occurred within a stable diffuse aurora. Conductivity calculations using the model results varied less than 15% from calculations using the radar measurements. The comparison was good even when the separation between the satellite and the radar was greater than 200 km. The fourth conjunction, for which the agreement was poor, occurred within the discrete aurora during a very active period when the ionospheric conditions were dynamic both spatially and temporally.