We present the results of modeling the radiation of a decaying plasma, formed by the processes of electron-ion recombination with the participation of three neon ions: the molecular ion Ne2+ and atomic ions Ne+ and Ne2+. Such a combination of ions, simultaneously participating in the formation of the plasma spectrum, was first discovered in the afterglow of a pulsed barrier discharge of a cylindrical geometry at neon pressures less than 1 Torr and an electron density[e] ≤ 4 × 1010 cm-3. The main attention is paid to the comparative analysis of the mechanisms of impact-radiation recombination of Ne+ and Ne2+ ions based on the numerical solution of the system of differential equations for the densities of ions and long-lived excited atoms in the afterglow, taking into account the main elementary processes in decaying plasma with pulsed "heating" of electrons. The regularities of electron temperature relaxation from discharge values of several electron volts to 300 K in the late afterglow are considered in particular details. Comparison of the model solutions with the spectral intensities measured by the multichannel photon counting method shows that, given their good agreement in the case of singly charged ions, an adequate description of the evolution of ionic lines requires expanding the available information on the recombination of Ne2+ ions.

The results of an experimental study and simulation of radiation generated by the processes of collisional-radiative recombination of neon ions Ne+ and Ne++ with electrons of the decaying plasma are presented. Plasma was created by a barrier discharge in a cylindrical glass tube with electrodes on its surface. Experimental conditions: neon pressure 0.65 Torr, electron density at the initial stage of the afterglow [e] ≈ (1 - 5) • 1011 cm-3. The main attention is paid to the comparative analysis of the collisional-radiative recombination of Ne+ and Ne++ ions based on the numerical solution of coupled differential equations for the densities of charged and long-lived excited particles and the electron temperature, taking into account the main elementary processes in decaying neon plasma. Comparison of the model solutions with the intensities of ionic and atomic spectral lines measured by the multichannel photon counting method indicates the need to refine the dependence of the rate of collisional-radiative recombination on the ion charge.