Measurement of Electron-Ion Recombination

Abstract

Microwave techniques are applied to the measurement of the recombination between electrons and positive ions. The measured recombination coefficients for monatomic gases range from 1.7\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}8}$ cc/ion-sec. for helium to 3\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}7}$ cc/ion-sec. for argon. The recombination coefficients for diatomic gases range from 2.5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ cc/ion-sec. for hydrogen to 2.8\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}7}$ cc/ion-sec. for oxygen. At electron temperatures of 300\ifmmode^\circ\else\textdegree\fi{}K, the recombination is found to be independent of pressure for the monatomic gases. A pressure dependence is observed in diatomic gases, the recombination increasing with increasing pressure in nitrogen and oxygen.