A detailed discussion of the N2(C 3IIu) and N2(X 1Σg+) vibrational temperatures in N2 glow discharges

A N-2 direct current discharge was studied by optical emission spectroscopy. Experimental parameters as gas How rate (Q), pressure (p) and current (1) were varied independently, covering the following range: 10 < I < 75 mA, 100 < Q < 1000 sccm and 1.7 < p < 10 torr, corresponding to the following plasma parameters: electron density in the range 10(9)-10(12) cm(-3) and reduced electric field between 3 x 10(-16) and 10(-15) V cm(-2). The N-2 (C (IIu)-I-3, upsilon'), N-2(X (1)Sigma(g)(+), upsilon) vibrational temperatures and the gas temperature were obtained from the first and second positive systems emissions. The N-2 (C (IIu)-I-3, upsilon') vibrational distributions did not exhibit a Boltzmann character. A linearization process was employed to such distributions allowing us to calculate the N-2(C (IIu)-I-3, upsilon') temperature. The N-2(X (1)Sigma(g)(+), upsilon) temperature was calculated from 9 the N-2(C (IIu)-I-3, upsilon') one on the basis of the Franck-Condon factors. Results and the method of vibrational temperature calculus are presented.