Abstract
High-spin states of nuclei were studied with the reactions NiSi,Kr, NiSi,Sr, and NiSi,Zr at 130 MeV beam energy. The Gammasphere array in conjunction with the charged-particle detector array Microball was used to detect rays in coincidence with evaporated light charged particles. The known , yrast bands were extended to at 20 MeV excitation energy. For all three nuclei, a number of positive- and negative-parity sidebands were established; altogether 15 new rotational bands were found. The data are discussed using the pairing-and-deformation self-consistent total Routhian surface (TRS) model: High-spin structures of Kr and Sr are governed by the shell gaps at large prolate deformation while Zr seems to exhibit shape coexistence. Nearly identical bands were established which may be explained as arising from the orbits acting as spectators at very elongated shapes. The experimental data in these nuclei are in good agreement with predictions of the TRS model using conventional like-nucleon pairing correlations.
- Received 19 February 1997
DOI:https://doi.org/10.1103/PhysRevC.56.98
©1997 American Physical Society