# Article

Plasma Investigations
2019. V. 57. № 3. P. 308–315
Korshunov O.V., Chinnov V.F., Kavyrshin D.I.
Highly ionized helium arc plasma. Determination of the temperature in nonequilibrium conditions and the effect of plasma microfields
Annotation
Methods are proposed for the spectral measurement of electron temperature $T_e$ in a highly ionized nonequilibrium He plasma at atmospheric pressure based on a comparison of the intensities of atomic and ionic lines with a whole complex of experimental data (primarily, $n_e$). The large energy gap between the emitting $\rm HeI$ and $\rm HeII$ excited levels (of more than $50$ eV) and allowance for the nonequilibrium manifested in the overpopulation of the atomic levels with respect to the ionic levels make it possible to make reliable and simple $T_e$ estimates, especially if the ionization energies of the emitting levels of the atom and the ion are close. For practical use, three pairs of $\rm HeI$ and $\rm HeII$ lines observed in the spectral range of $200$–$1100$ nm are recommended. The radial and temporal (upon the quasistationary pulsed heating of the electric arc plasma) dependences of $T_e$ are obtained in the range of axial values of $3.2$–$4.7$ eV.
Article reference:
Korshunov O.V., Chinnov V.F., Kavyrshin D.I. Highly ionized helium arc plasma. Determination of the temperature in nonequilibrium conditions and the effect of plasma microfields, High Temp., 2019. V. 57. № 3. P. 308