Electron-impact excitation of the lowest autoionizing states of alkalis using a distorted-wave method

Abstract

Atomic collisions involve scattering of projectiles by some target. The scattering can be done experimentally under certain laboratory conditions or modeled theoretically using known and reliable methods. From scattering a lot of information about the target and also the dynamics of the collision process can be obtained through determination of cross sections, alignment parameters and the angular correlation parameters. These information find application in various branches of physics, for instance, laser physics, biophysics and plasma physics. In this study, integral cross-sections, differential cross-sections, alignment and lambda parameters for electron-impact excitation of the lowest auto ionizing states of Li, Na and K have been calculated using Distorted-Wave method. We have applied a linear combination of static potentials of initial aruflinal target states as the final channel distortion potential and the static potential of the initial target state as the initial channel distortion potential. The wave functions used in this model are the multi zeta and the double zeta Hartree-Fock single electron wave functions. Numerical calculations have been performed using a modified program. The results of this study are compared with experimental and theoretical data available in literature. In case of sodium, our results predict the near threshold resonance which is observed in the experimental results.