Spectroscopic study and lifetime measurement of the 6d7p F-3(2)o state of radium

We report a method for the precision measurement of the oscillator strengths and the branching fractions of the decay channels of the 6d7p F-3(2)o state in Ra-226. This method exploits a set of metastable states present in Ra, allowing a measurement of the oscillator strengths that does not require knowledge of the number of atoms in the atomic beam. We measure the oscillator strengths and the branching fractions for decays from the 6d7p F-3(2)o state to the 7s6d D-3(1), 7s6d D-3(2), and 7s6d D-1(2) states and constrain the branching fraction to the 7s6d D-3(3) state to be less than 0.4% (68% confidence limit). The lifetime of the F-3(2)o state is determined to be 15 +/- 4 ns.