BAND CROSSING OBSERVED IN NEUTRON-RICH PD ISOTOPES VIA SPONTANEOUS FISSION OF CF-252

High spin excited states in neutron-rich nuclei Pd-112, Pd-114, Pd-116 have been investigated by measuring prompt gamma rays emitted from a Cf-252 spontaneous fission source. Two different measurements were performed. First, gamma-gamma coincidence data, necessary to determine the decay schemes, were obtained by using an array of 20 Compton-suppressed Ge detectors. Second, Z identification and the enhancement of a desired neutron channel were carried out using a x-n-gamma multiplicity spectrometer. Ground state bands have been extended to J(pi) = 10+ for 112Pd, and J(pi) = 12+ for 114Pd and 116Pd. Band crossings were observed in all three isotopes. It was found from cranked shell model calculations that these backbends are due to the alignment of two g9/2 protons. The measured energy levels were also compared with predictions of the interacting boson model.