Elastic Resonances in Electron Scattering from He, Ne, Ar, Kr, Xe, and Hg

Abstract

The transmission of electrons through the rare gases and mercury vapor has been examined as a function of electron energy, with energy resolution of about 0.04 eV. Many anomalies (resonances) localized in energy have been observed, totaling 11 in helium, six in neon, two each in argon and krypton, five in xenon, and 13 in mercury. The interpretation of these resonances in terms of compound negative ion formation is discussed, and in several cases electron configurations are assigned to the negative ions. In helium, neon, xenon, and mercury, sharp decreases in transmission are observed which are attributed to the onset of inelastic processes. Definite identification of the inelastic processes in the case of helium permits calibration of the absolute electron energy scale to within ±0.03 eV.