HYPERFINE-STRUCTURE MEASUREMENTS ON TRAPPED PB-II

The 6P3/2-6P1/2 magnetic dipole resonance transition in Pb+ has been observed by cw laser excitation of an ion cloud stored in a Paul trap and subsequent detection of the fluorescence radiation. From the hyperfine-structure splitting of the spectrum we determine the A factor for the ground state, A(P1/2) = 12.967(13) GHz, and the excited state, A(P3/2) = 0.580(3) GHz. From a contamination of Pb-208 in our sample we derived the Pb-207+-Pb-208+ isotope shift [DELTA-nu = 311(14) MHz]. A small electric quadrupole admixture giving rise to a DELTA-F = 2 component in the spectrum has been determined to be 6.4(0.5)% of the total transition amplitude.