Systematic study of near yrast band structures in odd-mass $^{125-137}$Pr and $^{127-139}$Pm isotopes

Abstract

In the present work, the basis space in the triaxial projected shell model approach is expanded to include three and five quasiparticle configurations for odd-proton systems. This extension allows to investigate the high-spin band structures observed in odd-proton systems up to and including the second band crossing region, and as a first major application of this development, the high-spin properties are investigated for odd-mass 125−137 Pr and 127−139 Pm isotopes. It is shown that band crossings in the studied isotopes have mixed structures with first crossing dominated by one-proton coupled to two-neutron configuration for the lighter isotopes which then changes to three-proton configuration with increasing neutron number. Further, γ-bands based on quasiparticle states are also delineated in the present work, and it is predicted that these band structures built on threequasiparticle configurations become favoured in energy for heavier systems in the high-spin region.