Relativistic distorted-wave collision strengths for [formula omitted] transitions in the 67 Li-like, F-like and Na-like ions with [formula omitted

Abstract

Relativistic distorted-wave collision strengths have been calculated for all possible Δn=0 transitions, where n denotes the valence shell of the ground level, in the 67 Li-like, F-like and Na-like ions with Z in the range 26≤Z≤92. This choice produces 3 transitions with n=2 in the Li-like and F-like ions, and 10 transitions with n=3 in the Na-like ions. For the Li-like and F-like ions, the calculations were made for the six final, or scattered, electron energies E′=0.008,0.04,0.10,0.21,0.41, and 0.75, where E′ is in units of Zeff2 Ry with Zeff=Z−1.66 for Li-like ions and Zeff=Z−6.667 for F-like ions. For the Na-like ions, the calculations were made for the six final electron energies E′=0.0025,0.015,0.04,0.10,0.21, and 0.40, with Zeff=Z−8.34. In the present calculations, an improved “top-up” method, which employs relativistic plane waves, was used to obtain the high partial-wave contribution for each transition, in contrast to the partial-relativistic Coulomb–Bethe approximation used in previous works by Zhang, Sampson and Fontes [H.L. Zhang, D.H. Sampson, C.J. Fontes, At. Data Nucl. Data Tables 44 (1990) 31; H.L. Zhang, D.H. Sampson, C.J. Fontes, At. Data Nucl. Data Tables 48 (1991) 25; D.H. Sampson, H.L. Zhang, C.J. Fontes, At. Data Nucl. Data Tables 44 (1990) 209]. In those previous works, collision strengths were also provided for Li-, F- and Na-like ions, but for a more comprehensive set of transitions. The collision strengths covered in the present work should be more accurate than the corresponding data given in those previous works and are presented here to replace those earlier results.