Response of Background Optical Emission to Ionospheric Heating by High-Power Radio Emission

The results of a numerical simulation of the dynamics of the airglow of the atomic oxygen red line (630 nm) due to ionospheric heating by high-power, high-frequency (HF) radio emission are presented. The simulation was based on a system that incorporates an equation for the electron temperature T e (thermal conductivity) with a localized heating source near the reflection point of the pump wave; an equation to balance the ion concentration in molecular oxygen O_2^ + , which emerges from the charge exchange reaction (О + + О 2 → O_2^ + + О); and an equation for the concentration of oxygen atoms in the excited state O( 1 D ), which results from the dissociative recombination ( O_2^ + + е − → О + О( 1 D )) and is responsible for the airglow. The height distributions of molecular (O 2 ) and atomic (O) oxygen were taken from the NRLMSISE-00 empirical model of the atmosphere, and the profiles of the electron content N e were taken from the International Reference Ionosphere (IRI) model modified according to the 2010 and 2012 experimental data from the SURA ionospheric heating facility. The results have been compared with experimental data. The calculations make it possible to interpret the experimentally observed suppression of the background airglow during ionospheric heating by a high-power radio wave and the “afterglow” effect upon the cessation of heating.