Shape Coexistence in Even-Even Ge Isotopes - Complete Spectroscopy with Coulomb Excitation -

Abstract

The characteristics of the low-lying levels in the doubly even Ge isotopes are studied by means of multiple Coulomb excitation experiments. The (Q2 ) values of two 0+ states in the Ge isotopes have shown the presence of the coexcistence of a spherical and deformed structures. The mixing between the regular and intruder structures is derived in a simple two states mixing model. The crossing of the two 0 + might take place; the intruder state might become the ground state in 70Ge.

Low-Energy Coulomb Excitation for the Shell Model

“…In the stable Ge isotopes, the Q 2 invariants extracted for the ground state and the 0 + 2 state via low-energy Coulomb excitation represent one of the strongest signatures of shape coexistence [21,22]. As shown in Figure 3a, the ground-state Q 2 values in [70][71][72][73][74][75][76] Ge are similar, 0.2-0.3 e 2 b 2 , while those of the 0 + 2 states evolve as a function of the neutron number.…”