Elastic Scattering Of Electron By Barium Atom Using Distorted Wave Method

ABSTRACT

Knowledge of differential and integral cross sections for electron scattering from atoms and molecules is very important for explanation and understanding of electron interaction with matter and for determining dynamics of collision processes. It is also important in the study of astrophysics, plasma physics and laser development. For the past three decades, experimental and theoretical results for electron-barium elastic scattering have been reported however, these results are inconsistent. Theoretical results do not agree with the experimental results and theoretical results do not agree among themselves. In this study the distorted wave method has been applied to calculate the differential and total cross section for elastic scattering of electron by barium atom at electron impact energies of 10-200 eV and a range of scattering angles of (θ) from 0° to 180°. Being an elastic scattering process, both initial and final distortion potentials are taken as static potential of a barium atom in the initial state. The distorted waves are determined by partial wave expansion method by expanding them in terms of spherical harmonics while the radial equation corresponding to distorted waves are evaluated using Numerov method. A computer program DWBA1, for e - - H scattering was modified for the process under consideration and used for the above calculation. The results for differential and integral cross section are compared with experimental and theoretical results available. The comparison of the integral cross section results with other theoretical and experimental results shows that the present results are in good qualitative agreement with experimental and most of theoretical results. At lower incident energies 10-20 eV the present DCS are not in satisfactory agreement with the experimental and theoretical results. However at higher incident energies, 30-100 eV the present DCS are in satisfactory agreement with other theoretical and experimental results. So, it can be said the present distorted wave method works well for electron-barium elastic scattering and recommend be extended to metals such as gadolinium and radium.