HIGH-PRECISION RELATIVE OSCILLATOR STRENGTH MEASUREMENTS IN SM I BY ABSORPTION-SPECTROSCOPY

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