Role of excited N2 in the production of nitric oxide

Excited N-2 plays a role in a number of atmospheric processes, including auroral and dayglow emissions, chemical reactions, recombination of free electrons, and the production of nitric oxide. Electron impact excitation of N-2 is followed by radiative decay through a series of excited states, contributing to auroral and dayglow emissions. These processes are intertwined with various chemical reactions and collisional quenching involving the excited and ground state vibrational levels. Statistical equilibrium and time step atmospheric models are used to predict N-2 excited state densities and emissions ( as a test against previous models and measurements) and to investigate the role of excited nitrogen in the production of nitric oxide. These calculations predict that inclusion of the reaction N-2[A(3)Sigma(+)(u)] + O, to generate NO, produces an increase by a factor of up to three in the calculated NO density at some altitudes.