Heating of ambient electrons in thermosphere under varying solar activity conditions

Abstract

The suprathermal electron flux plays a very important role in the production of various airglow emissions. The solar extreme ultra violet (EUV) photons and X-rays are mainly responsible for the production of suprathermal electrons in the atmosphere. These suprathermal electrons further cause heating of ambient electrons in the thermosphere. In the present study, the heating rate of ambient electrons in the thermosphere under the effect of varying solar activity has been studied. The suprathermal electron flux has been calculated as a function of suprathermal electron energy. The fluxes have been calculated at various levels of solar activity and various geographic locations during a period of five years (2001-2005). This flux has been further used to calculate the ambient electron heating rate in the thermosphere. It has been found that the maximum electron heating rate is near 30°N latitude. It has been found that the maximum electron heating rate does not vary linearly with F10.7 solar index. The altitude of the peak heating rate does not show any appreciable variation with the solar activity at a fixed latitude. The altitude of peak electron heating rate moves upwards as the latitude increases from equator towards pole at the fixed value of F10.7 solar index.