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The low-spin collective excitations of even-even Pd nuclei in the A ≈ 110 mass region indicate a structural transition from an anharmonic vibrator to a gamma-soft rotor. This observation is supported by recent calculations of the potential energy surfaces using different types of mean field approaches. In particular, prolate-to-oblate shape transition has been predicted at 111Pd [1]. Experimental evidence for a shape change or shape coexistence can be obtained by high-spin studies of these transitional nuclei. Band crossings in the odd-N Pd nuclei are especially important to understand the origin of the alignments. No band structures built on the low-lying states were known in heavier odd Pd nuclei (A≥109). High-spin states in these nuclei cannot be populated using fusion-evaporation reactions. The heavier neutron-rich 112,114,116Pd nuclei have been studied from spontaneous fission of 252Cf [2]. In this work the less neutron-rich Pd nuclei have been produced as fission fragments following the fusion reactions 28Si + 176Yb at 145 MeV. The 28Si beam was provided by the Vivitron accelerator in Strasbourg. Gamma rays were recorded with the EUROGAM2 array [3]. The level schemes were constructed by examining γ- spectra extracted from two and three dimensional matrices.

The present work reports on a study of high spin states in 190Pt On the basis of TRS calculation, an interpretation is proposed for the new structures as well as for the previously known 10- isomer.