The aim of the work was to find the optimal way to set up an experiment for spectroscopic study of the dissociative recombination of molecular ions with electrons in low electron density plasma at low gas pressure. In such an experiment, the influence of inelastic atom- atom collisions on the distribution of the DR flux over the excited atomic levels can be excluded. The first results of an experiment on combining a low-frequency barrier discharge (DBD) in neon at a pressure of less than 1 Torr with a pulsed radio-frequency (RF) induction discharge are presented. To create the plasma, we used DBD in a cylindrical glass tube with an inner diameter of 3.9 cm, which forms the spatial distribution of electron density with a minimum on the axis of the tube. The evolution of such a spatial distribution due to ambipolar diffusion in the initial stage of plasma decay provides an influx of charged particles to the center of the discharge tube, which increases the afterglow duration and helps to overcome the difficulties of detecting weak plasma radiation. The specific features of the DBD also appeared in the ionic composition of the plasma, which contained, in addition to Ne + and Ne2 +, tht Ne ++ ions, whose recombination with electrons significantly enriched the afterglow spectrum in the short-wavelength region. An RF discharge was used for pulsed heating of electrons in the afterglow. It is shown that, in accordance with the ionic composition of the plasma, the radiation of a decaying plasma is presented by three groups of spectral lines with characteristic time behavior and the electron temperature dependence. The advantages of the proposed approach for studying the mechanism of dissociative recombination are discussed.
Original languageEnglish
Article number045022
Pages (from-to)045022
Number of pages9
JournalPlasma Sources Science and Technology
Volume29
Issue number4
Early online date12 Mar 2020
DOIs
StatePublished - Apr 2020

    Scopus subject areas

  • Condensed Matter Physics

    Research areas

  • Collisional-radiative recombination, Dielectric-barrier discharge, Dissociative recombination, Low-pressure plasma, Molecular ions, Optical emission spectroscopy, Radio-frequency discharge, ION-CONVERSION PROCESSES, low-pressure plasma, optical emission spectroscopy, dielectric-barrier discharge, collisional-radiative recombination, MOLECULAR-IONS, AFTERGLOW, TOTAL RATE COEFFICIENT, molecular ions, ELECTRON-TEMPERATURE DEPENDENCE, radio-frequency discharge, NEON, EXCITED-STATE PRODUCTION, ATOMS, BARRIER DISCHARGE, HELIUM, dissociative recombination

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