The low-lying structures of the self-conjugate (N=Z) nuclei 8241Nb41 and 8643Tc43 have been investigated using isomeric-decay spectroscopy following the projectile fragmentation of a 107Ag beam. These represent the heaviest odd–odd N=Z nuclei in which internal decays have been identified to date. The resulting level schemes shed light on the shape evolution along the N=Z line between the doubly-magic systems 5628Ni and 10050Sn and support a preference for T=1 states in Tz=0 odd–odd nuclei at low excitation energies associated with a T=1 neutron–proton pairing gap. Comparison with Projected Shell Model calculations suggests that the decay in 82Nb may be interpreted as an isospin-changing K isomer.
This is the author’s version of a work that was accepted for publication in Physics Letters B. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Physics Letters B, 660, 4, 2008, 10/1016/j.physletb.2008.01.017