EVOLUTION OF PLASMA RADIATION FROM BARRIER DISCHARGE IN LOW-PRESSURE NEON. ATOMIC SPECTRUM

The results of a spectroscopic study of the plasma created by a barrier discharge in low-pressure neon are presented, reflecting the evolution of the mechanisms of population of excited levels of the Ne* atom and Ne⁺* ion depending on the observation time relative to the beginning of the discharge. Analysis of the emission spectrum, correlated with measurements of the time dependences of the intensities of spectral lines, allows us to indicate four stages of spectrum evolution: direct population by electron impact in the active stage (discharge), followed by a stepwise population at its end with a transition, as the electron temperature relaxes, to recombination afterglow. The latter, depending on the gas pressure and the initial electron density, can also contain two stages – the initial one, with the predominance of the mechanism of collisional-radiative recombination of Ne⁺⁺ and Ne⁺ ions with electrons as the source of population of all excited levels of the Ne⁺* ion and neon atom observed in the experiment, and the final stage, the radiation in which is associated with the population of a limited group of levels due to the dissociative recombination of Ne₂⁺ molecular ions with electrons. The main attention in the work is paid to the population kinetics of the levels of configurations 2p⁵3p and 2p⁵4p of the neon atom.