Resonance Structure of Cross-Sections of Slow-Electron Scattering by Calcium Atom

Authors

  • V.F. Gedeon Uzhhorod National University
  • V.Yu. Lazur Uzhhorod National University
  • S.V. Gedeon Uzhhorod National University
  • O.V. Yehiazarian Uzhhorod National University

DOI:

https://doi.org/10.15407/ujpe67.3.161

Keywords:

electron, calcium atom, scattering, excitation, ionization, R-matrix with B-splines method, nonorthogonal orbitals, resonances

Abstract

The extended BSR-version of the R-matrix method has been applied to systematically analyze the electron scattering by neutral calcium atoms at collision energies up to 4.3 eV. The strong coupling method with the sets of term-dependent nonorthogonal orbitals and the spline representation of the basis functions are used to accurately represent the target wave functions. The strong-coupling expansion included 39 bound states of the neutral calcium atom, which cover all its states from the ground one to 4s8s 1S. The complex resonance structure of the angleintegrated total cross-sections of the elastic e+Ca scattering and the electron-impact excitation of the 4s4p 3Po, 3d4s 3De, 3d4s 1De, 4s4p 1Po, and 4s5s 3Se states of a Ca atom are studied in detail. The observed structures are associated with particular autodetachment states of the “incident electron + Ca atom” system. The positions and widths of detected resonances are determined, and their spectroscopic classification is carried out.

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Published

2022-05-19

How to Cite

Gedeon, V., Lazur, V., Gedeon, S., & Yehiazarian, O. (2022). Resonance Structure of Cross-Sections of Slow-Electron Scattering by Calcium Atom. Ukrainian Journal of Physics, 67(3), 161. https://doi.org/10.15407/ujpe67.3.161

Issue

Section

Optics, atoms and molecules