High-precision relative oscillator strength measurements in Sm I by absorption spectroscopy

We have measured relative oscillator strengths for a series of electric dipole transitions in Sm I using laser absorption spectroscopy. The 154Sm -152Sm isotope shift in the transitions is also obtained from the data. The transitions originate from levels of the ground term, and are near companions to magnetic dipole transitions of interest for atomic parity non-conservation. The relative f values have been converted to absolute values using the known lifetime of one of the Sm energy levels, for which our relative measurements give the branching ratios for transitions to the ground term (neglecting weak infra-red transitions to higher-lying states)