Atomic data from the IRON Project

Abstract

As part of the IRON Project, radiative rates have been calculated for the E1, E2 and M1 transitions within the complex in ions of the boron isoelectronic sequence (). The computations have been carried out with the atomic structure code superstructure which facilitates the generation of extended radiative datasets including configuration interaction, Breit–Pauli relativistic contributions and semi-empirical term-energy corrections. By means of extensive comparisons with the available datasets for this sequence, with detailed single-ion calculations and recent experiments, we have been able to assign accuracy ratings to the present A-values. We find that in general the spin-allowed and spin-forbidden E1 transitions are accurate to 10% and 20%, respectively, except for a few transitions in ions with that are perturbed by admixture with low-lying states (e.g. 2s) and for those affected by the avoided crossing of the 2s2pS1/2 and P1/2 which takes place at . It is concluded that, statistically, the present dataset is the most accurate to date for this astrophysically relevant sequence.