E1, M1, E2 transition energies and probabilities of W⁵⁴⁺ ions

A comprehensive theoretical study of the E1, M1, E2 transitions of a Ca-like tungsten ion is presented. Using the multi-configuration Dirac–Fock (MCDF) method with a restricted active space treatment, the wavelengths and probabilities of the M1 and E2 transitions between the multiplets of the ground state configuration ([Ne]3s²3p⁶3d²) and of the E1 transitions between [Ne]3s²3p⁵3d³ and [Ne]3s²3p⁶3d² have been calculated. The results are in reasonable agreement with available experimental data. The present E1 and M1 calculations are compared with previous theoretical values. For E2 transitions, the importance of electron correlation from 3s and 3p orbitals is pointed out. Several strong E1 transitions are predicted, which have potential advantages for plasma diagnostics. (paper)