Effects of energetic electron and proton precipitations on thermospheric nitric oxide cooling during shock-led interplanetary coronal mass ejections

The distributions are incorporated into the Global Ionosphere-Thermosphere Model. The results show that electrons play a dominant role to NO cooling, but protons are also important and contribute to up to a quarter of NO cooling by electrons and ions combined. NO cooling enhancement during the events is proportional to the level of energy flux and is dominated by the electrons in the energy band of 1.4-3.1 keV.

Both total electron content (TEC) and NO cooling enhance at the source regions, but they have different lifetime and correlation with the particle precipitations. Generally, NO cooling and TEC enhancements have a positive correlation with the precipitating energy. Cross correlation shows that particle precipitations have more instantaneous impact on TEC while it takes longer for the atmosphere to heat up for cooling to proceed.