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Current issue   Ukr. J. Phys. 2016, Vol. 61, N 11, p. 950-955
https://doi.org/10.15407/ujpe61.11.0950    Paper

Simulik V.M.1, Zajac T.M.2, Tymchyk R.V.3

1 Institute of Electron Physics, Department of the Theory of Elementary Interactions,
Nat. Acad. of Sci. of Ukraine
(21, Universytets’ka Str., Uzhgorod 88000, Ukraine; e-mail: vsimulik@gmail.com)
2 Uzhgorod National University, Chair of Electron Systems
(13, Kapitul’na Str., Uzhgorod 88000, Ukraine)
3 Institute of Electron Physics, Department of Electron Processes, Nat. Acad. of Sci. of Ukraine
(21, Universytets’ka Str., Uzhgorod 88000, Ukraine; e-mail: vsimulik@gmail.com)

Choice of the Wave Function for the Helium Ground State for Precision Calculations of Quasistationary State Parameters

Section: Atoms and Molecules
Original Author's Text: Ukrainian

Abstract: In the problems of ionization of atoms by photons and electrons, the necessity of choosing the multiparametric wave functions for the description of an atom in the ground state has been substantiated. The helium atom is taken as an example. The energies, widths, and partial widths of the lowest 1p autoionizing state of helium, located above the excited ions formation threshold, are calculated. The results obtained with the use of different ground state wave functions are compared. It is shown that, contrary to the total widths of autoionizing states, the partial widths are substantially different for different ground-state wave functions.

Key words: autoionizing states, quasistationary states, overlapping configurations, multiparametric wave functions.

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