High-spin states and superdeformation in the proton-neutron interacting boson model

The superdeformed band in 192Hg has a similar structure to the ground-state bands in several actinide nuclei, particularly to the uranium isotopes, such as 232U. We report on neutron-proton Interacting Boson Model (IBM-2) calculations for the uranium isotopes and make a specific comparison of the superdeformed band in 192Hg with the ground-state band in 232U. Theoretically these two bands should have the same structure in the Interacting Boson Model, because they contain the same number of active proton bosons and neutron bosons, with the superdeformed band in 192Hg being treated as a 4p-6h excited state in terms of fermions. Results of a no new free parameter IBM-2 configuration mixing calculation for the (0p-2h), (2p-4h) and (4p-6h) configurations in 192Hg are presented. (orig.)