Speaker
Description
Lifetimes of low-spin excited states in $^{98}$Zr were measured using the recoil-distance Doppler-shift technique and the Doppler-shift attenuation method. The nucleus of interest was populated in a $^{96}$Zr($^{18}$O,$^{16}$O)$^{98}$Zr two-neutron transfer reaction at the Cologne FN Tandem accelerator giving access to the low-sping structure of the nucleus. Lifetimes of six excited states, of which four unknown, were measured. The deduced $B(E2)$ values were compared with Monte-Carlo shell model and interacting boson model with configuration mixing calculations. Both approaches reproduce well most of the data but leave challenging questions regarding the structure of some low-lying states. Most notable is the low collectivity of the $B(E2; 2^+_1 \rightarrow 0^+_2)$ which is not predicted by both models.
