N₂⁺/N₂ratio and temperature measurements based on the first negative N₂⁺and second positive N₂overlapped molecular emission spectra

The and molecular emission spectra are frequently observed simultaneously in plasmas containing nitrogen. Relative band intensities of these systems are very sensitive to a variation of the ratio and temperature. The spectrum, emitted between 3800 and 4000 A, has been used to measure rotational and vibrational temperatures, and to estimate the ratio when the electron temperature is known, in different plasma sources (Glidarc, ac discharge between tips). The proposed method is based on a point-to-point comparison of an experimentally measured spectrum with the computer-simulated one.