Measurement of Electron-Ion Recombination

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×{}10^-8 cc/ion-sec. for helium to 3×{}10^-7 cc/ion-sec. for argon. The recombination coefficients for diatomic gases range from 2.5×{}10^-6 cc/ion-sec. for hydrogen to 2.8×{}10^-7 cc/ion-sec. for oxygen. At electron temperatures of 300^∘{}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.