1202.6154 (A. Dijon et al.)

Discovery of a new isomeric state in $^{68}$Ni: Evidence for a
highly-deformed proton intruder state    [PDF]

A. Dijon, E. Clément, G. De France, G. De Angelis, G. Duchêne, J. Dudouet, S. Franchoo, A. Gadea, A. Gottardo, T. Hüyük, B. Jacquot, A. Kusoglu, D. Lebhertz, G. Lehaut, M. Martini, D. R. Napoli, F. Nowacki, S. Péru, A. Poves, F. Recchia, N. Redon, E. Sahin, C. Schmitt, M. Sferrazza, K. Sieja, O. Stezowski, J. J. Valiente-Dobon, A. Vancraeyenest, Y. Zheng

We report on the observation of a new isomeric state in $^{68}$Ni. We suggest that the newly observed state at 168(1) keV above the first 2$^+$ state is a $\pi(2p-2h)$ 0$^{+}$ state across the major Z=28 shell gap. Comparison with theoretical calculations indicates a pure proton intruder configuration and the deduced low-lying structure of this key nucleus suggests a possible shape coexistence scenario involving a highly deformed state.

View original: http://arxiv.org/abs/1202.6154