The level structure of 83Zr

The level structure of 83Zr was investigated via the fusion-evaporation reaction 54Fe(32S,2pn)83Zr at beam energies between 105 and 120 MeV using in-beam γ-ray spectroscopy techniques. γ transitions from the decay of 83Zr were unambiguously identified by means of recoil-γ and neutron-γ coincidence experiments. The decay scheme was constructed on the basis of Compton suppressed γγ coincidences, delayed γγ coincidences and angular distribution measurements. A total of 34 transitions were identified connecting 26 new energy levels and the previously known ground state. The lifetimes of two low-lying isomeric states were determined. A decoupled positive parity band built on the odd g9/2 neutron configuration was observed up to spin 37/2 h with the first band crossing due to proton alignment showing a sharp backbend at hw ∼ 0.5 MeV. A strongly coupled negative parity band based on a 5/2- bandhead was observed up to spin 35/2 h. The angular momentum alignment is discussed and compared to neighboring nuclei. A theoretical analysis was performed using the Woods-Saxon cranking model. The results of the calculation are consistent with the experimental findings for 83Zr and its neighbors. Triaxial shapes are predicted for all observed bands in 83Zr. At higher angular momenta a transition to well deformed prolate bands including the h11/2 intruder orbitals is expected