Atomic data from the IRON Project^*

XXXIII. Radiative rates for the intercombination transitions in the carbon isoelectronic sequence

¹ Centro de Física, Instituto Venezolano de Investigaciones Científicas (IVIC), PO Box 21827, Caracas 1020A, Venezuela
² URA 173 (associée au CNRS et à l'Université Paris 7) et DAEC, Observatoire de Paris, F-92195 Meudon, France
³ Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK

Send offprint request to: C.J. Zeippen

Received: 11 June 1998
Accepted: 31 August 1998

Abstract

Radiative decay rates are computed with the atomic structure code superstructure for the , and 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 Z. By extensive comparisons with other theoretical datasets and measurements of the radiative lifetime and the PP 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 A-values belonging to transitions to the are not expected to be accurate to more than 20%.