Currently there is no accurate theoretical approach available for treating fully differential cross sections (FDCS) for low-energy electron-impact ionization of large molecules. For high incident energies, the plane wave impulse approximation (PWIA) generally yields good agreement with experimental data. In this paper, the distorted wave impulse approximation (DWIA) is used to calculate FDCS for low-energy electron-impact ionization of N2. To perform the necessary average over all molecular orientations, we propose an orientation average (OA) approximation. Although the DWIA results represent an improvement over the PWIA for intermediate energies, an improved theory is necessary for lower energies. However, the OA approximation will greatly simplify the evaluation of improved theories for lower energies.
J. Gao et al., "Fully Differential Cross Sections for Low-Energy Electron-Impact Ionization of Nitrogen Molecules," Physical Review A: Atomic, Molecular, and Optical Physics, American Physical Society (APS), Jan 2005.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevA.72.020701
National Science Foundation (U.S.)
Library of Congress Subject Headings
Differential cross sections
Electron impact ionization
Article - Journal
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