Evidence for coexisting shapes in ${}^{98}$Zr through lifetime measurements

Abstract

The lifetimes of first excited 2${}^{+}$, 4${}^{+}$ and 6${}^{+}$ states in ${}^{98}$Zr were measured with the Recoil-Distance Doppler Shift method in an experiment performed at GANIL. Excited states in ${}^{98}$Zr were populated using the fission reaction between a 6.2 MeV/u ${}^{238}$U beam and a ${}^9$Be target. The $\gamma$ rays were detected with the EXOGAM array in correlation with the fission fragments identified in mass and atomic number in the VAMOS++ spectrometer. Our result shows very small B(E2;2${}_1^{+}$ $\to$ 0${}_1^{+}$) value in ${}^{98}$Zr thereby confirming the very sudden onset of collectivity at $N=60$. The experimental results are compared to large-scale Monte Carlo Shell model and beyond mean field calculations. The present results indicate coexistence of two additional deformed shapes in this nucleus along with the spherical ground state.

References in corpus (2)

• First Measurement of Collectivity of Coexisting Shapes based on Type II Shell Evolution: The Case of ${}^{96}$Zr
• Structural evolution in $A\approx 100$ nuclei within the mapped interacting boson model based on the Gogny energy density functional

Cited by in corpus (13)

• Intertwined Quantum Phase Transitions in the Zr Isotopes
• Shape coexistence in even-even nuclei: A theoretical overview
• Zr Isotopes as a region of intertwined quantum phase transitions
• The subtle connection between shape coexistence and quantum phase transition. The Zr case
• Tests of collectivity in ${}^{98}$Zr by absolute transition rates
• Nuclear shape evolution and shape coexistence in Zr and Mo isotopes
• Shape and multiple shape coexistence of nuclei within covariant density functional theory
• Shape phase transitions in odd-A Zr isotopes
• Fast trajectory reconstruction techniques for the large acceptance magnetic spectrometer VAMOS++
• Evolution of the phenomenologically determined collective potential along the chain of Zr isotopes
• Shape evolution in even-mass ${}^{98-104}$Zr isotopes via lifetime measurements using the $\gamma \gamma$-coincidence technique
• Coupling between collective modes in the deformed ${}^{98}$Zr nucleus: Insights from consistent HFB+QRPA calculations with the Gogny interaction
• The pervasiveness of shape coexistence in nuclear pair condensates