The yrast sequence of the neutron-rich dysprosium isotope ${}^{168}\mathrm{Dy}$ has been studied using multinucleon transfer reactions following collisions between a 460-MeV ${}^{82}\mathrm{Se}$ beam and an ${}^{170}\mathrm{Er}$ target. The reaction products were identified using the PRISMA magnetic spectrometer and the $\gamma$ rays detected using the CLARA HPGe-detector array. The $2^{+}$ and $4^{+}$ members of the previously measured ground-state rotational band of ${}^{168}\mathrm{Dy}$ have been confirmed and the yrast band extended up to ${10}^{+}$. A tentative candidate for the $4^{+}\to 2^{+}$ transition in ${}^{170}\mathrm{Dy}$ was also identified. The data on these nuclei and on the lighter even-even dysprosium isotopes are interpreted in terms of total Routhian surface calculations and the evolution of collectivity in the vicinity of the proton-neutron valence product maximum is discussed.

• Received 25 September 2009

DOI:https://doi.org/10.1103/PhysRevC.81.034310