Abstract
Experiments were carried out at the Wright Nuclear Structure Laboratory (WNSL) at Yale University using the 21MV ESTU Tandem Van de Graaff accelerator with the purpose of studying the high spin states of 8839Y and 8839Y. A beam of 18O impinged at a laboratory energy of 60 MeV on a 600 μg/cm2 74Ge target with a thick (10 mg/cm2) 197Au backing. This experiment was performed with the specific aim of accessing medium to high spin states of the nucleus of interest. A second experiment was undertaken to populate the nucleus of interest in higher spin states by impinging a 18O beam on a thin 62 μg/cm2 76Ge target with a 20 μg/cm2 carbon backing at a laboratory beam energy of 90 MeV. Gamma rays emitted following the decay of excited states in 88,89Y and other nuclei populated in the reactions were measured using the YRAST ball detector array, consisting of 10 Compton suppressed HPGe clover detectors. There are 17 previously unreported 7 rays identified and placed in the respective level schemes in the current work for 88, 89Y. In conjunction with the experimental study presented in the body of this work, nuclear shell model calculations using the code NuShellX with a truncated valence space have also been performed in an attempt to describe the single-particle make-up of the states observed.