Coulomb Excitation of Stable Even-Even zn Isotopes

Multiple Coulomb excitation of ^66,68Zn was carried out. The experimental data were analyzed with the least-squares search code GOSIA. E2 matrix elements and quadrupole moments of 2_1^ + states were obtained. The ground band structures are explained to some extent with the asymmetric rotor model (ARM) and the interacting boson model (IBM) in O(6) limit. Potential energy surfaces (PES) calculated with the Nilsson-Strutinsky model show γ-unstability for ⁶⁶Zn and shallow two minima for ⁶⁸Zn. According to the experimental results and induction from the theoretical calculations, it seems that ^66,68Zn would be explained with such a model with soft triaxial potential.