Evidence for deformation in 113-116Cd isotopes

Abstract

High-spin states in 113−116 Cd have been investigated with the fusion-fission reaction 28 Si + 176 Yb at 145 MeV. The experiment has been performed with the Eurogam2 array. New rotational bands based on two quasi-particle states have been observed for even-even cadmium isotopes. A new level scheme based on the 11/2 − isomeric state is proposed for 115 Cd and the one of 113 Cd has been extended to spin (31/2 − ). The decoupled bands identified in both odd-A nuclei are interpreted as being built upon a low-Ω h 11/2 quasi-neutron configuration. Microscopic Hartree-Fock + BCS calculations confirm the prolate deformation in this mass region especially for the odd cadmium isotopes. PACS. 21.60.Ev Collective models -21.60.Jz Hartree-Fock -23.20.Lv Gamma transitions and level energies -25.70.Jj Fusion and fusion-fission reactions -27.60.+j 90 ≤ A ≤ 149