Simultaneous optogalvanic and laser-induced fluorescence investigation in the neon positive column

The optogalvanic effect in the positive column of a neon discharge has been investigated both experimentally and theoretically. A mechanically chopped dye laser was tuned to several 1si–2pj neon transitions (Paschen notation). Optogalvanic spectra and their dependence on the current (1–5 mA) for the 594.5-nm optogalvanic resonance were analyzed. Furthermore, fluorescence and laser-induced fluorescence from the discharge have been examined. A general model based on the steady-state solution of rate equations has been developed in order to interpret the optogalvanic and fluorescence measurements. Good agreement between optogalvanic measurements and theoretical predictions was obtained, but there is a discrepancy between the theoretical prediction and the observed laser-induced fluorescence, which exposes the limitations of the model.