[en] Aims. We report on the theoretical and experimental lifetimes of Ta II, and calculated branching fractions for selected transitions. Methods. The theoretical data are obtained by means of a relativistic Hartree-Fock method with detailed attention to correlation effects. The experimental lifetimes are measured with the time-resolved, laser-induced, fluorescence technique.
Results. The calculated results are in good agreement with both previously known and new experimental lifetimes. New transition probabilities have been deduced for a set of Ta II transitions of astrophysical interest.