Description
As part of the IRON Project, radiative rates have been calculated for the E1, E2 and M1 transitions within the n=2 complex in ions of the boron isoelectronic sequence (6<=Z<=28). 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 Z<=7 that are perturbed by admixture with low-lying n=3 states (e.g. 2s^2^3l) and for those affected by the avoided crossing of the 2s2p^2^ ^2^S1/2 and ^2^P1/2 which takes place at Z~22. It is concluded that, statistically, the present dataset is the most accurate to date for this astrophysically relevant sequence.
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