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

Abstract

Energy levels, radiative transition probabilities and autoionization rates for 1s22s22p63l′nl (n = 3–13, l ⩽ n − 1), 1s22s22p64l′nl (n = 4–7, l ⩽ n − 1) and 1s22s22p53l′3l″nl (n = 3–4, l ⩽ n − 1) states in Mg-like tungsten (W62+) are calculated using the Hartree–Fock-relativistic method (COWAN code), the multiconfiguration relativistic Hebrew University Lawrence Atomic Code (HULLAC code) and the relativistic many-body perturbation theory method (RMBPT code). Autoionizing levels above the thresholds 1s22s22p63l and 1s22s22p64l are considered. 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 first excited odd- and even-parity states. It is shown that the contribution of the highly excited states is very important for the calculation of total DR rates. Contributions to DR rate coefficients from the excited 1s22s22p63l′nl states with n ⩾ 14 and 1s22s22p64l′nl states with n ⩾ 8 and additionally from core-excited 1s22s22p53l′3l″nl states with n ⩾ 5 are estimated by extrapolation of all atomic parameters. The orbital angular momentum quantum number l distribution of the rate coefficients shows two peaks at l = 2 and l = 5. The total DR rate coefficient is derived as a function of electron temperature. The dielectronic satellite spectra of W62+ are important for L-shell diagnostic of very high-temperature laboratory plasmas such as future ITER plasmas.