Excitation energies, radiative and autoionization rates, dielectronic satellite lines, and dielectronic recombination rates for excited states of Na-like W from Ne-like W

Abstract

Energy levels, radiative transition probabilities, and autoionization rates for 1 s 2 2 s 2 2 p 5 3 l ′ nl , 1 s 2 2 s 2 p 6 3 l ′ nl ( n = 3 – 7 , l ⩽ n - 1 ) and 1 s 2 2 s 2 2 p 5 4 l ′ nl , 1 s 2 2 s 2 p 6 4 l ′ nl ( n = 4 – 6 , l ⩽ n - 1 ) states in Na-like tungsten ( W 63 + ) are calculated. Cowan’s relativistic Hartree–Fock method, the relativistic multiconfiguration method implemented in the Hebrew University Lawrence Livermore Atomic Code, and the relativistic many-body perturbation theory method, are used. Autoionizing levels above the threshold 1 s 2 2 s 2 2 p 6 are considered. It is found that configuration mixing [ 3 sns + 3 pnp + 3 dnd ] , [ 3 snp + 3 pns + 3 pnd + 3 dnp ] plays an important role for all atomic characteristics. Also strong mixing between states with 2 s and 2 p holes ( 1 s 2 2 s 2 2 p 5 3 l 1 nl 2 + 1 s 2 2 s 2 p 6 3 l 3 nl 4 ) occurs. Branching ratios relative to the first threshold and intensity factors are calculated for satellite lines, and dielectronic recombination (DR) rate coefficients are determined for the excited 1 s 2 2 s 2 2 p 6 nl ( n = 3 – 7 , l ⩽ n - 1 ) states. It is shown that the contribution of the highly excited states is very important for calculation of total DR rates. Contributions from the autoionizing states 1 s 2 2 s 2 2 p 5 3 l ′ nl , 1 s 2 2 s 2 p 6 3 l ′ nl ( n ⩾ 8 ) and 1 s 2 2 s 2 2 p 5 4 l ′ nl , 1 s 2 2 s 2 p 6 4 l ′ nl ( n ⩾ 7 ) to the DR rate coefficients are estimated by extrapolation of all atomic parameters. The orbital angular momentum ( l) distribution of the rate coefficients shows a peak at l = 2 . The total DR rate coefficient is derived as a function of electron temperature. The dielectronic satellite spectra of W 63 + are important for L-shell diagnostics of very high-temperature laboratory plasmas such as future ITER fusion plasmas.