Solar influence on the redline dayglow emission under equinox conditions

Abstract

In the present paper the results of the modeled emission rates of redline dayglow emission are presented under equinox conditions as a function of F10.7 solar index. The Solar2000 EUV (extreme ultra violet) flux model is used in the model. It is for the first time that the Solar2000 EUV flux model is being used in the modeling of redline dayglow emission. The model is tested with the WINDII (wind imaging interferometer) observations of redline dayglow emission. It has been found that the modeled emission rates are in good agreement with WINDII observations over a wide range of altitudes. The model is also tested for peak emission rate using the empirical formula of Zhang and Shepherd (2004). The volume emission rate is calculated at various locations and local times under varying solar activity conditions using this model. An analytical formula which gives the latitudinal variation of peak emission rate is obtained from the modeled volume emission rates under equinox conditions. The redline dayglow emission intensities are studied under equinox conditions as a function of F10.7 solar index. It is found that the intensity does not vary linearly with F10.7 index and becomes more or less saturated when the F10.7 index is greater than 200.