Recombination Spectrum and Electron Density Measurements in Neon Afterglows

Abstract

The spectrum emitted by the recombination of positive ions and electrons in the afterglow of a pulsed microwave discharge through neon has been studied as a function of time. Simultaneous electron density measurements on the plasma were made by the cavity resonant frequency shift method, and the recombination coefficient was calculated from these data. The total radiated visible light was found to be proportional to the square of the observed electron density. The observation of light intensities allowed recombination measurements to be carried out at electron densities much too high to be observed directly by the cavity resonant frequency shift method. The relative intensities of several strong lines in the spectrum remained essentially constant during the afterglow, while the relative intensities of several others showed consistent changes.