Open AccessOscillator strengths for the helium isoelectronic sequence
Author(s) -
A. W. Weiss
Publication year - 1967
Publication title -
journal of research of the national bureau of standards. section a. physics and chemistry
Language(s) - English
Resource type - Journals
eISSN - 2376-5704
pISSN - 0022-4332
DOI - 10.6028/jres.071a.023
Subject(s) - helium , sequence (biology) , wave function , dipole , atomic physics , physics , ion , chemistry , quantum mechanics , biochemistry
Variational wavefunctions have been computed for the 1 1 S, 2 1, 3 S, 2 1, 3 P, 3 1, 3 P, and 3 1, 3 D terms of ions in the helium isoelectronic sequence from He through Ne +8 . The trial functions are Hylleraas type expansions, explicitly involving r 12 , and with expansion lengths of around 50 terms, differing slightly for the different states. Oscillator strengths have been computed for all the allowed transitions by both the dipole length and velocity formulas. Agreement between these forms, comparisons with very accurate data for neutral helium, and the accuracy of the computed energies all point to considerable reliability of the results for the entire sequence, probably around 5 percent, if not better.