Shape coexistence and low-lying collective states in A ≈ 100 Zr nuclei

Abstract

Collective quadrupole and octupole excitations in even 94−00Zr nuclei are studied within the fully microscopic generator-coordinate method using a basis generated by the selfconsistent Hartree-Fock BCS method. Results with the effective interaction SkM ∗ correctly describe the experimentally observed spherical to deformed shape transition at A = 100. Properties of low-lying O +, 2 + and 3 − states are analysed. The measured B(E3) value of 65 single-particle units in 96Zr is underestimated in our calculations. Various aspects of our theoretical approach are discussed, including Skyrme force parametrization, treatment of pairing and one- versus two-dimensional description of octupole excitations.