The lifetimes of first excited 2+, 4+ and 6+ states in 98Zr were measured with the Recoil-Distance Doppler Shift method in an experiment performed at GANIL. Excited states in 98Zr were populated using the fission reaction between a 6.2 MeV/u 238U beam and a 9Be target. The γ 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;21+→ 01+) value in 98Zr 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.
@article{arxiv.1902.02637,
title = {Evidence for coexisting shapes in $^{98}$Zr through lifetime measurements},
author = {Purnima Singh and W. Korten and T. W. Hagen and A. Görgen and L. Grente and M. -D. Salsac and F. Farget and E. Clément and G. de France and T. Braunroth and B. Bruyneel and I. Celikovic and O. Delaune and A. Dewald and A. Dijon and J. -P. Delaroche and M. Girod and M. Hackstein and B. Jacquot and J. Libert and J. Litzinger and J. Ljungvall and C. Louchart and A. Gottardo and C. Michelagnoli and C. Müller-Gatermann and D. R. Napoli and T. Otsuka and N. Pillet and F. Recchia and W. Rother and E. Sahin and S. Siem and B. Sulignano and T. Togashi and Y. Tsunoda and Ch. Theisen and J. J. Valiente-Dobon},
journal= {arXiv preprint arXiv:1902.02637},
year = {2019}
}