Two-quasiparticle K isomers within the covariant density functional theory

Abstract

Two-quasiparticle excitations of medium mass nuclei with well-defined axial deformation are studied within the covariant density functional framework. The evolution of high-$K$ isomers is analyzed in a self-consistent axially symmetric relativistic Hartree-Bogoliubov calculation using the blocking approximation. The occurrence of the ${6}^{+}$ and ${8}^{\ensuremath{-}}$ low-energy high-$K$ isomers in the region from Er to Pb ($68\ensuremath{\le}Z\ensuremath{\le}82,\phantom{\rule{0.28em}{0ex}}98\ensuremath{\le}N\ensuremath{\le}112$) is evaluated and compared to available data. The importance of the quasiparticle spectrum in the energy evolution of the high-$K$ states is discussed in detail.