Wavelengths and transition rates fornl–n′l′ transitions in Be-, B-, Mg-, Al-, Ca-, Zn-, Ag- and Yb-like tungsten ions

We present a comprehensive theoretical study of atomic characteristics of eight isoelectronic sequences of tungsten ions in a broad range of wavelengths and transitions. In particular, excitation energies, oscillator strengths and transition probabilities are calculated for nl – n ' l ' transitions in W 70 + , W 69 + , W 62 + , W 61 + , W 54 + , W 44 + , W 27 + and W 4 + ions. Atomic structure and radiative characteristics of Be-like ([He]2 lnl ', n = 2, 3), B-like ([He]2 l 2 l '2 l ''), Mg-like ([Ne]3 l 3 l '), Al-like ([Ne]3 l 3 l '3 l ''), Ca-like ([Ar]3d4 l ), Zn-like ([Ni]4 l 4 l '), Ag-like [Kr]4d 10 nl ) and Yb-like ([Xe]4f 14 5 l 6 l ') tungsten ions are computed by the relativistic many-body perturbation theory (RMBPT) method. The calculations start from a 1s 2 Dirac–Fock potential for Be- and B-like W, from the 1s 2 2s 2 2p 6 Dirac–Fock potential for Mg- and Al-like W; from the 1s 2 2s 2 2p 6 3s 2 3p 6 and 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 Dirac–Fock potentials for Ca- and Zn-like W, respectively. Evaluation of properties of Ag-like and Yb-like ions starts from a Dirac–Fock potential with only partially filled n = 4 shell (1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 6 4d 10 ) and n = 5 shell (1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 6 4d 10 4f 14 5s 2 5p 6 ), respectively. First-order perturbation theory is used to obtain intermediate coupling coefficients, and second-order RMBPT is used to determine the matrix elements. The contributions from negative-energy states are included in the second-order E1 matrix elements to achieve agreement between length-form and velocity-form amplitudes. Our calculations present benchmark data for many yet unmeasured properties of tungsten ions and are in particular important in diagnostics of tungsten plasma of a broad range of temperatures as well as for future ITER plasmas.