Homologous states and the structure of nuclei in the lead region

The structure of both low-lying and highly excited states and electromagnetic transitions in Pb-206 and Tl-205 has been studied within the framework of the shell model. The calculation predicts the occurrence of states in Pb-206 With a structure homologous to parent states in Tl-205, a phenomenon experimentally reported in these systems via ((p) over right arrow, alpha) reactions, in analogy with other regions of the mass table. This feature is not restricted to configurations where the two neutron holes are coupled to angular momentum zero, but also applies to higher configurations corresponding to angular momentum recoupling of the two neutron holes. The calculated results, obtained with both a modified surface delta interaction and Kuo-Herling interaction, are in good agreement with the experimental data, further supporting the ability of these interactions to describe nuclear properties in the lead region.