Atomic data for doubly-excited states [formula omitted] of He-like ions and [formula omitted] of Li-like ions with [formula omitted] and [formula omitted

Abstract

The wavelengths and radiative transition probabilities for transitions 2lnl′→1snl″, 2lnl′→1s2l″, 1s2lnl′→1s2nl″, 1s2lnl′→1s22l″, and the autoionization decay probabilities for doubly-excited states 2lnl′, 1s2lnl′ were calculated in He-like and Li-like ions with atomic numbers Z=6–36 for the principal quantum number n=2,3 and the orbital quantum one l=0–2. The calculations were carried out by means of the MZ code based on the Z-expansion method. Relativistic corrections were taken into account within the framework of the Breit operator. The main difference with previous calculations by MZ code consists in accounting for the first order corrections in powers of 1/Z, corresponding to the screening effects, in calculations of autoionization rates. New data for comparatively large rates are of about 20%–50% less as compared to previous ones and are in an agreement within 10% with the results of calculations made by the methods based on multi-configuration wave functions with non-relativistic and relativistic orbitals. Some refinements and corrections concerning the energies and radiative transition probabilities were also introduced in the MZ code. In this paper the main formulas used in a modified MZ code and the data needed for the description of dielectronic satellites with n=2,3 are given.