ИСТИНА

Energetic electrons in tens keV energy range are responsible for a whole range of ionospheric effects through ionization and excitation of atmospheric neutrals. The particle-produced ionospheric effects consist in increases of plasma density and positive ionospheric storms, ionospheric irregularities and scintillations, polar cap absorption effects and aurora/optical emissions. The ionospheric effects with different spatial and temporal scales become significant mainly during solar and geomagnetic disturbances, when intense electron fluxes penetrate into the atmosphere in a wider latitudinal range. From middle latitudes to the polar cap region, the ionospheric effects are produced by precipitating energetic electrons at heights of the bottom-side ionosphere. From low to middle latitudes, the ionospheric effects are produced by quasi-trapped energetic electrons at heights of the topside ionosphere. We show important distinctions in time and space between ionospheric effects caused by the quasi-trapped and precipitating energetic electrons.