Oscillator strengths and transition probabilities from the Breit–Pauli R-matrix method: Ne IV

• The first application of BPRM method for accurate E1 transitions in Ne IV is reported.
• Amount of atomic data (n going up to 10) is complete for most practical applications.
• The calculated energies are in very good agreement with most observed levels.
• Very good agreement of A-values and lifetimes with other relativistic calculations.
• The results should provide precise nebular abundances, chemical evolution etc.

The atomic parameters–oscillator strengths, line strengths, radiative decay rates (AA), and lifetimes–for fine structure transitions of electric dipole (E1) type for the astrophysically abundant ion Ne IV are presented. The results include 868 fine structure levels with n≤n≤ 10, l≤l≤ 9, and 1/2≤J≤≤J≤ 19/2 of even and odd parities, and the corresponding 83,767 E1 transitions. The calculations were carried out using the relativistic Breit–Pauli R-matrix method in the close coupling approximation. The transitions have been identified spectroscopically using an algorithm based on quantum defect analysis and other criteria. The calculated energies agree with the 103 observed and identified energies to within 3% or better for most of the levels. Some larger differences are also noted. The AA-values show good to fair agreement with the very limited number of available transitions in the table compiled by NIST, but show very good agreement with the latest published multi-configuration Hartree–Fock calculations. The present transitions should be useful for diagnostics as well as for precise and complete spectral modeling in the soft X-ray to infra-red regions of astrophysical and laboratory plasmas.