Competition between strong and de-coupling in odd-odd mass nuclei

Competition of strong and decoupling is studied systematically for odd-odd mass nuclei as a function of the position of the Fermi surfacesε _F (π) andε _F (υ) and the deformationsβ andγ. As an example we use⁸⁰Br. For a prolate deformation the odd proton likes to decouple while the odd neutron couples strongly. This favours a ground state angular momentum of 5 to 6. The strong coupling is described by the admixture of ad _5/2 nucleon. Only for the neutrons the admixture is so appreciably that it affects the spectrum and improves the agreement between theory and experiment for⁸⁰Br.