Spectroscopic study of argon DC glow discharge

In this paper, emission spectra of both positive column (PC) and negative glow (NG) regions of the dc glow discharge have been measured at different pressures and currents. The intensity of the lines in the NG is in the order of five times of that corresponding lines' intensity in the PC region. It is found that the line intensity increases linearly with the discharge current, while it increases as P-alpha with the gas pressure. The electron temperature T-e has been estimated using the line-to-line-intensity-ratio technique. It is found that T-e derived by this technique generally decreases with the pressure. Also, T-e in NG region is about 3/2 of that in the PC.