0000000000371199
AUTHOR
S. Chmel
First observation of excited states in 184Pb: spectroscopy beyond the neutron mid-shell
Excited states have been identified for the first time in 184Pb, the first even-even Pb isotope beyond the 82 < N < 126 mid-shell, using the recoil-decay tagging (RDT) technique. A collective band built on the first-excited 2+ state has been observed. This resembles those seen in 186,188Pb and the Hg isotones, and can thus be associated with a prolate-deformed shape. Variable moment of inertia (VMI) fits of the prolate 0+ level energies in 184,186,188Pb indicate that the minimum appears at N= 103, the same neutron number at which the corresponding minimum in Hg isotopes is observed.
Conversion electron spectroscopy of magnetic-rotational bands in 197Pb and 199Pb
Magnetic–rotational bands in the nearly spherical nuclei 197Pb and 199Pb and their decay to the normal states have been investigated by in–beam conversion electron spectroscopy following (heavy ion,xn) reactions. The expected M1 multipolarity of the in–band transitions has been confirmed for the strongest bands and the multipolarity of several transitions in the decay of the bands has been determined.