Optogalvanic effect and measurement of gas temperature in an abnormal glow discharge

Axial distribution of the gas temperature in an abnormal glow discharge in argon is simultaneously determined by laser optogalvanic and absorption spectroscopy methods. Temperature distributions obtained by two different methods are in a fair agreement except in the boundary region between the cathode fall and the negative glow. Systematically lower temperature in this region obtained by optogalvanic spectroscopy is a consequence of the nature of optogalvanic effect, which, in some circumstances, cannot be identified with spectral line profile. (c) 2006 American Institute of Physics.