Measurement of lifetimes and tensor polarizabilities of odd-parity states of atomic samarium

A systematic measurement of the lifetimes and tensor polarizabilities of the lowest-lying odd-parity levels of Sm I was performed. The lifetimes were measured by detecting time-resolved fluorescence following pulsed-laser excitation of atoms in an atomic beam; polarizabilities were measured employing the method of Stark-induced quantum beats. An analysis of the data is undertaken to find the best even-parity candidate states for an atomic electric dipole moment (EDM) measurement. For the most favorable candidate state ({sup 7}G{sub 1}), the electron EDM enhancement factor is evaluated to be in the range {vert_bar}R{vert_bar}{approx}100{endash}3800. Critical analysis of the present data along with earlier results in Sm shows the necessity of a term reassignment for several odd-parity states. This term reassignment is also used in an estimate of the parity-nonconserving {sup 7}F{sub 0}{r_arrow}{sup 7}G{sub 1} amplitude. {copyright} {ital 1999} {ital The American Physical Society}