DETERMINATION OF THE EXCITATION TEMPERATURE IN A NONTHERMODYNAMIC-EQUILIBRIUM HIGH-PRESSURE HELIUM MICROWAVE PLASMA TORCH

This paper analyzes the influence of the departure from thermodynamic equilibrium on three spectroscopic methods for determining the excitat ion temperature: the classical Boltzmann plot method, the method of ab solute intensity measurements, and the method of the ratio of atomic t o ionic lines for one element. Use of these methods is illustrated wit h experiments conducted in a helium microwave plasma in nonthermodynam ic equilibrium produced by an axial injection torch at atmospheric pre ssure. The excitation temperature was determined at a variable microwa ve power and different positions along the flame. The results are disc ussed in terms of the atomic-state distribution function (ASDF) calcul ated for the plasma.