Study of the Pressure and Temperature Dependence of Electron-Ion Recombination in Neon

Abstract

Conventional microwave and mass-spectrometric techniques have been used to study the loss rate of electrons and ions in the afterglow following microwave discharges in neon. Under the conditions of the experiment, the afterglow decay rate is controlled by the recombination of electrons with the only observed ion species, ${\mathrm{Ne}}_2^{+}$, yielding a recombination coefficient which has a value of $\alpha \left({{\mathrm{Ne}}_2}^{+}\right)=(1.8\mathrm{}\pm 0.2)\times {10}^{-7\mathrm{}}$ ${\mathrm{cm}}^3$/sec at 295°K and a temperature dependence of $T_g^{-0.42\mathrm{}\pm 0.04}$ over the range covered, 295-503°K. At any given temperature, the measured recombination rates show no systematic dependence on the neon gas pressure over the range used, 8-30 Torr, indicating that the observed recombination process is a two-body reaction. Temporal mass analysis shows similar decay rates for the ${\mathrm{Ne}}_2^{+}$ ions and for the electrons over the major portion of the afterglow.