Benchmarking Atomic Data from Large-scale Multiconfiguration Dirac–Hartree–Fock Calculations for Astrophysics: S-like Ions from Cr ix to Cu xiv

Abstract

Abstract We present a consistent set of calculated energies and E1, M1, E2, M2 radiative transition data for the main n = 3 levels from the 3s 23p 4, 3p 6, , , , , and configurations for S-like ions from Cr ix to Cu xiv. The fully relativistic multiconfiguration Dirac–Hartree–Fock method implemented in the GRASP2K code is used to perform the present calculations. The excitation energies of the lowest 47 levels from the , , and configurations, producing the strongest lines, are found to be in good agreement, reaching spectroscopic accuracy, with the latest experimental values for Fe xi evaluated by Del Zanna. Our energies can reliably be used to identify in astrophysical and laboratory spectra the levels in other S-like ions, which are mostly unknown. On the contrary, significant discrepancies with the 3s3p 43d levels were found, emphasizing the need for more detailed experimental studies. A few new tentative identifications are suggested. The benchmarks we present indicate that our consistent set of radiative data is accurate and can be used for spectral line modeling.