HYPERFINE-STRUCTURE INVESTIGATIONS AND IDENTIFICATION OF NEW ENERGY-LEVELS IN THE IONIC SPECTRUM OF PM-147

Hyperfine structure splittings have been measured for 75 lines of sing ly ionized promethium (PmII)-Pm-147 with a hollow cathode discharge an d a Fabry-Perot interferometer. Magnetic dipole and electric quadrupol e splitting factors A and B have been determined for 10 levels of the 4f(5)6s configuration, 2 levels of 4f(5)5d, and 57 upper undesignated levels. The A-factors are in general agreement with calculated values. With the aid of Hartree-Fock calculations and Zeeman-effect data, fou r new levels of the 4f(5)(H-6)5d K-7 term were located. The strong lin es terminating on these K-7 levels originate from levels of 4f(5)(H-6) 6p I-7, which were already known, but had not been designated. An unid entified line at 556.17 nm previously observed with collinear laser io n-beam spectroscopy is now classified as 4f(5)(H-6)5d K-7(6)-4f(5)(H-6 )6p I-7(5).