Radiative rates for the intercombination transitions in the carbon isoelectronic sequence |
C. Mendoza, C.J. Zeippen and P.J. Storey |
Astronomy & Astrophysics Supplement Series, 1999, Vol.135, pp.159-169 |
Radiative decay rates are computed with the atomic structure code
SUPERSTRUCTURE for the 2s2p S -
2s2p P,P and D intercombination transitions
of the carbon isoelectronic sequence (). Contributions from
configuration interaction and relativistic corrections are carefully
studied, in particular the spin-spin interaction that is shown to be of
considerable importance for low . By extensive comparisons with other
theoretical datasets and measurements of the S radiative
lifetime and the B =
branching ratio, we are able to assign accuracy ratings to the present
transition probabilities. The transitions to the ground term are believed
to be accurate to better than 10% whereas the smaller -values belonging
to transitions to the D are not expected to be accurate to more than
20%.