Spectroscopic study and lifetime measurement of the 6d7p 3F2o state of radium

Abstract We report a method for the precision measurement of the oscillator strengths and the branching fractions of the decay channels of the 6d7p 3F2o state in 226Ra. 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 3F2o state to the 7s6d 3D1, 7s6d 3D2, and 7s6d 1D2 states and constrain the branching fraction to the 7s6d 3D3 state to be less than 0.4% (68% confidence limit). The lifetime of the 3F2o state is determined to be 15 ± 4 ns.