Electron capture and loss by metastable and ground-state N+ions in collision with inert gases

Abstract

The electron-capture cross sections in inert-gas targets for ground and metastable states of N⁺ ions have been measured in the energy range of 2-30 keV for ground-state, and 5-20 keV for metastable-state ions. Results obtained by three different experimental methods (initial growth, beam attenuation and condenser measurements) coincide above 15 keV, showing a negligible influence due to scattering. An analysis of the correlation between electron-capture cross sections and the corresponding energy defects for the three possible metastable states of N⁺, ¹D, ¹S and ⁵S, suggests that the metastable beam component observed in the present experiments is the ⁵S state. Collisionally induced de-excitation of the metastable ion has been measured. The de-excitation cross section has been found to be of the same order of magnitude as the electron-capture cross section of the metastable ion.