Ionosphere produced through the precipitation of electrons of several hundred electronvolts

An enhancement of the electron density in the topside ionosphere in the cusp region may be ascribed to relatively low energy electrons incoming from outer space through the polar cusp. This short note describes a theoretical estimate of the ionospheric structure resulting from the precipitation of electrons having a specified incident energy ranging from 100 eV to 1 keV. Electrons having incident energies around 300 eV are found to be most effective in producing the F2 region.