Electronically excited molecular nitrogen and molecular oxygen in the high-latitude upper atmosphere

Abstract

Abstract. Relative vibrational populations of triplet B3Πg, W3Δ,sub>u, B'3Σu− states of N2 and the b1Σg+ state of O2 are calculated for different altitudes of the high-latitude upper atmosphere during auroral electron precipitation. It is shown that collisional processes cause a wavelength shift in the distribution of relative intensities for 1PG Δv=3 sequence of N2. The calculation of relative populations for vibrational levels v=1–5 of the b1Σg+ state in the auroral ionosphere has not given an agreement with experimental results. Preliminary estimation of the contribution of the reaction O2++NO to the production of O2(b1Σg+) on the basis of a quantum-chemical approximation does not allow for an explanation of the observable vibrational population of the b1Σg+ state in the aurora.