FINE-STRUCTURE ANALYSIS OF THE (5D-I(6S)(5) LEVELS OF TA)

The fine structure of the prominent even levels of the neutral tantalu m atom has been analyzed by simultaneous parametrization of one- and t wo-body interactions for the model space (5d+6s)(5). The analysis was stimulated by the current discovery of several energy levels. It was p ossible to clear the configurations and designations of the energy lev els given in commonly used tables. Magnetic-dipole hyperfine interacti on constants A and electric-quadrupole hyperfine interaction constants B were calculated using the calculated eigenfunctions and adjusting r adial integrals in a least-squares procedure which compares the calcul ated A- and B-constants with the experimental values. The rms error of this fitting procedure confirms the quality of the fine structure ana lysis. Moreover, wavenumbers and hyperfine constants of 52 further lev els, up to now unidentified, are predicted.