Lifetimes and branching ratios of excited states in La-, Os-, Lu-, Lr-, and Pr-

Relativistic configuration-interaction calculations have been performed for all possible E1, M1, and E2 transitions between bound anion states of La- and Os-. We pay particular attention to E1 transitions in each case that may be of use in laser cooling of these anions. Although the La- transition energy is approximately one-third of the Os- transition, our results indicate that the Einstein A coefficient is nearly two orders of magnitude larger, which would lead to more efficient laser cooling. We have also explored long-lived opposite-parity excited states in Lu- and Lr- which are restricted to M2 decay by selection rules. Finally, in Pr-, we find sufficient mixing between a weakly bound excited 4f25d26s2 state with a nearby 4f36s26p resonance to result in a lifetime similar to that of the other excited anion states, despite the fact that the dominant configurations of these M1 and E2 transitions differ by two electrons.