HYPERFINE STRUCTURE OF BA 2-RESONANCE LINES AND QUADRUPOLE MOMENTS OF ODD BARIUM ISOTOPES

By means of a photoelectric registrating Fabry-Pérot-interferometer and using enriched Ba-isotopes the hyperfine structure of the barium II-resonance lines 6 p2P3/2,1/2-6 s2P1/2, λ λ4554; 4934 å has been investigated. The following results were obtained by digital data processing of the registrated interference curves:A(135Ba, 6 s2S1/2)=119.78(10) mK, A(137Ba, 6 s2S1/2)=133.94(11) mK, A(135Ba, 6 p2P1/2)=22.14 (8) mK, A(135Ba, 6 p2P3/2)=3.77(7) mK, and B(135Ba, 6 p2P3/2)=2.1 (3) mK. For the quadrupole moment of135Ba we calculated the value Q(135Ba)=0.17(2) · 10-24 cm2 (without Sternheimer correction). This result should not be strongly affected by perturbations in the p-terms of alcalilike spectra of heavy elements and by the uncertainty of the relativistic corrections. The isotope shift of the odd Ba-isotopes with respect to138Ba has been remeasured. © 1968 Springer-Verlag.