Temporal evolution of the electron density in high-pressure electron-beam-excited xenon plasmas

Abstract

Measurements of the free-free absorption coefficient in high-pressure (50–400 psia) e-beam-excited rare-gas plasmas have been used to deduce the temporal evolution of electron density in these systems. The measurements were carried out using a focused CO2 laser beam passing through the excited region of the plasma. Comparison of theory and experiment in the early afterglow, where Penning ionization of excimers dominates the electron production, yields a room-temperature rate coefficient of 8×10−11 cm3/sec for this process in xenon.