Interplanetary Ionization by Solar Extreme Ultraviolet Radiation.

Abstract

From recent rocket monochromator measurements of solar photon fluxes, ( , between 1300 and 60 A around 200 km, the fluxes o characteristic of the upper F2-region and interplanetary space near the earth are estimated by assuming some reasonable spectral attenuation factors / o due to the atmospheric absorption above the point of observation. Ionization rates in terms of are estimated for H, 0, N, and N2. The estimated total ionization rate for the hydrogen atom of about S X 10- per second implies a fractional ionization of at least 99.9 per cent for total hydrogen particle number densities of less than about 500/cm3.