Nuclear Structure of High Spin States

Microscopic nuclear shell model calculations have been advancing in capability over the last 40years. Florida State University's experimental nuclear structure group has participated in this advancement with the introduction of the FSU interaction in 2019. To provide new data and test out the theoretical predictions of the FSU interaction the excited, high spin structure of two nuclei are studied. The first, 37Ar, was studied using high resolution gamma spectroscopy following fusion evaporation compound reaction. This data was from an experiment at Argonne National Lab in 2017 with GRETINA (Gamma-Ray Energy Tracking In-beam Nuclear Array). Results presented herein show excellent agreement with nuclear states calculated with the FSU interaction. Several gamma transitions and levels not published before the start of the analysis are pointed out along with the next member of the yrast band. The second nucleus, 29Si, was studied using a direct reaction, 27Al(α, d)29Si. Of particular interest for this dissertation the (α, d) reaction was first studied by a group at Berkeley lab, who showed it selectively populates particular states [1]. Importantly the most strongly populated state by (α, d) is also the yrast fully aligned state of particular interest for comparison to the FSU interaction. Deuteron spectra of 27Al(α, d)29Si is presented up to the deuteron separation energy. Results of spectroscopic factor calculations are presented for deuteron cluster formation. A candidate peak for the fully aligned state is found at 13.7 MeV. Results from the study of both nuclei are presented in comparison to the FSU interaction. Agreement is found between FSU interaction and both nuclei for states along and near the yrast band. The fully aligned state in 29Si shows slight disagreement with the FSU interaction in absolute value, but on a relative basis the agreement is consistent with previous results from other nuclei lower in excitation energy, like 37Ar