Electron impact single and double ionization cross sections of Hg atoms

Theoretical studies of electron impact single and double ionization cross sections of Hg atoms have been performed in the binary encounter approximation. Direct double ionization has been investigated in the modified double binary encounter model. Accurate expression of sigma(Delta E) cross section for energy transfer Delta E and the Hartree-Fock velocity distributions for the target electrons have been used throughout the calculations. The present results of single ionization cross sections are in good agreement with the experimental observations. In the case of double ionization, the theoretical cross sections for direct double ionization show overall satisfactory agreement with the experiment. The calculated single and direct double ionization cross sections substantiate the viewpoint that only the direct processes lead to double ionization of Hg and there is no role of Auger effect concerning the measured data of double ionization.