Dissociative Recombination of Electrons withHe2+

Experimental results are reported which conclusively show that diatomic molecular helium ions recombine dissociatively with electrons. It is shown that dissociative recombination accounts for at least half of the total electronic recombination of ${\mathrm{He}}_2^{+}$ at a temperature of 300°K and in the pressure range from 15 to 55 Torr. The experimental technique which was used in this work includes measurement of the perturbation of the $2{}_{}{}^3{}_{}{}^{}S$ metastable density which results from a time-dependent perturbation of the electronic recombination coefficient.