Electronic kinetics of molecular nitrogen and molecular oxygen in high-latitude lower thermosphere and mesosphere

Abstract. Total quenching rate coefficients of Herzberg states of molecular oxygen and three triplet states of molecular nitrogen in the collisions with O₂ and N₂ molecules are calculated on the basis of quantum-chemical approximations. The calculated rate coefficients of electronic quenching of O₂* and N₂* molecules show a good agreement with available experimental data. An influence of collisional processes on vibrational populations of electronically excited N₂ and O₂ molecules is studied for the altitudes of high-latitude lower thermosphere and mesosphere during auroral electron precipitation. It is indicated that molecular collisions of metastable nitrogen N₂(A³Σ_u*) with O₂ molecules are principal mechanism in electronic excitation of both Herzberg states c¹Σ_u^&minus, A'³Δ_u, A³Σ_u⁺ and high vibrational levels of singlet states a¹Δ_g and b¹Σ_g⁺ of molecular oxygen O₂ at these altitudes.