A detailed discussion and supplemental experimental information on the electron capture and ${\mathrm{\beta }}^{+}$ decay schemes of ${}_{}{}^{153}{}_{}{}^{}\mathrm{Er}$ and ${}_{}{}^{157}{}_{}{}^{}\mathrm{Yb}$ proposed in our previous publications are included. The three-quasiparticle state and single-proton states assigned to ${}_{}{}^{153}{}_{}{}^{}\mathrm{Ho}$ have been reproduced by a shell model calculation. The extracted quenching factor for the three-quasiparticle state was determined to be 10. The existence of the two bands in ${}_{}{}^{157}{}_{}{}^{}\mathrm{Tm}$ has been explained by a triaxial deformation of the ground state of this nucleus. The experimental evidence from systematic behavior of the compiled low-energy levels indicates that the ground-state shapes change from spherical to deformed between neutron numbers N=86 and 88 in both the odd Ho and odd Tm isotopic chains. © 1996 The American Physical Society.

• Received 11 May 1995

DOI:https://doi.org/10.1103/PhysRevC.54.1481