Self-consistent kinetic model of the short-lived afterglow in flowing nitrogen

A detailed kinetic model for the flowing nitrogen microwave discharge and post-discharge is developed with the aim of gaining a deeper understanding into the processes responsible for the formation of the short-lived afterglow of nitrogen and for the enhancement of the concentration of N-2(A(3)Sigma(u)(+)) metastable, measured at approximately the same position in Sadeghi et al (2001 J. Phys. D: Appl. Phys. 34 1779). The present work shows that the peaks observed in the afterglow, for the density of molecules in radiative N-2(B(3)Pi(g)) and N-2(+)(B(2)Sigma(u)(+)) and metastable N-2(A(3)Sigma(u)(+)) states, can be explained as a result of a pumping-up phenomenon into the vibrational ladder produced by near-resonant V-V energy-exchange collisions, involving vibrationally excited molecules N-2(X(1)Sigma(g)(+), v) in levels as high as v similar to 35. The present predictions are shown to be in good agreement with the measured concentrations for N-2(A(3)Sigma(u)(+)) metastables and N(S-4) atoms, and with the emission intensities of 1(+) and 1(-) system bands of N-2.