Kinetic model and spectroscopic measurement of NO (A, B, C) states in low-pressure N2–O2 microwave discharge

Abstract

A self-consistent kinetic model is developed to study the atomic and molecular processes in the microwave discharge plasma of N2–O2 mixtures. We focus on the NO A 2Σ+, B 2Π, and C 2Π states in the mixture discharge. We find good agreement between the calculated and experimental NO A 2Σ+ densities. On the other hand, the radiation bands from the NO B 2Π and C 2Π states are observed only when the oxygen partial pressure is less than 3%. We discuss the de-excitation processes for the NO B 2Π and C 2Π states in this low-pressure plasma. We also propose that the de-excitation processes involve collision with O2 X for these levels, which can explain the observed spectral disappearance.