Atomic and molecular processes in lightning-induced sprite events

摘要

Lightning discharge temporarily produces strong electric field in the middle and upper atmosphere, which accelerates ambient electrons and causes optical emission called sprites through the electron collisions with neutrals (e.g., N2, O2, and O). The electron collisions dominant in the phenomena also generate metastable species initiating chemical reactions. For numerical study, we use (1) the cross section data of electron-neutral collisions to calculate the electron energy distributions in sprites and (2) the Einstein and quenching coefficients to calculate the intensity of optical emissions. Finally, it is pointed out that the uncertainty of cross section data used in the sprite study is the most critical problem for the correct estimation of chemical effects of sprite events.