07/29/2022
By E.J. Gass
Date: Aug. 3, 2022
Time: 2 p.m.
Location: Pinanski Hall, Room 200
Title: Gamma-Ray Spectroscopy of Sr-94 from Beta-Decay of Rb-94
Abstract: The decay of 94Rb into 94Sr is a process involving β-delayed neutron emission which is of particular interest due to its applications for nuclear reactor control. Previous experiments have also identified 94Sr as a nucleus in which γ-decay competes with neutron emission above the neutron separation energy, which is an extremely unusual phenomenon with potential implications for nuclear structure. The CARIBU (Californium Rare Isotope Breeder Upgrade) at Argonne National Laboratory's ATLAS (Argonne Tandem Linac Accelerator System) facility was used to produce a 94Rb beam. The beam was incident on a 35 mm aluminized mylar tape, which was used with the SATURN (Scintillator And Tape Using Radioactive Nuclei) system to prevent a buildup of activity. SCANS (Small CLYC Array for Neutron Scattering) and the X-Array were used to detect neutrons and γ-rays. This thesis concerns a spectroscopic analysis of the γ-rays detected by the X-Array. The level scheme of 94Sr was extended to 6519.8 keV, which is close to the neutron separation energy of 6.8 MeV and significantly higher than the previously-identified 6063.7 keV. Many newly-observed γ-rays were identified depopulating newly-suggested levels, which together indicate that the β-decay strength is higher around the neutron separation energy of 94Sr than previously suspected.
Committee Chair: Partha Chowdhury, Department of Physics and Applied Physics, University of Massachusetts Lowell
Commitee Members:
Erin Bertelsen, Department of Physics and Applied Physics, University of Massachusetts Lowell
Andrew Rogers, Department of Physics and Applied Physics, University of Massachusetts Lowell