Hydrogen ion study by incoherent scatter (IS) method. Comparison of results taken by Kharkov IS radar with data from Arecibo and Millstone Hill radars, Atmosphere Explorer satellites and model

摘要

Investigation of hydrogen ion behavior in topside ionosphere with the Kharkov IS radar is conducted by the POLITE CEDAR program. Program aim is the study of light ion morphology and dynamics for refinement of the global topside ionosphere models and forecast of the "space weather". In this paper, the H~+ density data of radars at Kharkov, Arecibo and Millstone Hill are compared at altitudes up to 1000―1300 km for winter and summer, minimum and maximum of solar activity. The measurements showed that height and diurnal variations of H~+ concentration over eastern and western hemispheres were generally in close agreement. It is revealed a strong longitudinal variation of H~+ ion fraction that is accounted for different magnetic flux tube volumes due to the offset between the geographic and geomagnetic poles. The Kharkov radar data are also compared with results taken from the Atmosphere Explorer (AE) database and FLIP model calculations, for midlatitude region, noon and midnight local time, at solar minimum. Comparisons show that H~+ height distributions good agrees and corresponds close conditions of ionosphere-plasmasphere interaction. At the same time the model and AE data are lower than measured densities at Kharkov that can be explained by geophysical condition difference.