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The nuclear structure of the⁹⁸Zr nucleus was studied through theβ⁻decay of⁹⁸Y_g.s.at the TRIUMF-ISAC facility. The use of the 8π γ-ray spectrometer with its ancillary detectors SCEPTAR and PACES enabled γ-γ and γ-e⁻coincidence measurements as well as γ-γ angular correlations. The level spin assignments and transition mixing ratios obtained in this study were in good agreement with previous results. Furthermore, 12 previously unknown states in the low-energy region of⁹⁸Zr were identified, including the 0⁺₅and 0⁺₆levels at 2418 and 2749 keV, respectively. The 2⁺and I=1 natures for multiple newly observed and previously known (but not firmly assigned) states have been established. Additionally, the previously assumed pureE2 character of the 2⁺₂→ 2⁺₁367.8-keV transition was confirmed. 

Nuclear shape coexistence is a widespread but not yet well understood phenomenon. Electric monopole (E0) transitions are a particularly sensitive probe of shape coexistence. The firstE0measurements on the Cr isotopes were performed at The Australian National University, but were hampered by missing and imprecise data of the key spectroscopic quantities such as level lifetimes. To address these needs, the low-lying states in⁵²Cr were investigated at the University of Kentucky Accelerator Laboratory with inelastic neutron scattering. γ-ray angular distribution and excitation function measurements were performed to determine level lifetimes, spins and parities, transition mixing ratios, and γ-ray branching ratios. We present new level lifetimes for three states in⁵²Cr along with the implications for E0 transition strengths and shape coexistence in⁵²Cr. 

Neutron elastic scattering cross sections on natural carbon serve as a reference standard in the incident energy range 10 eV to 1.8 MeV. The 2017 standards evaluation [1, 2] is 0.5 to 2.0% higher in that energy range than the 2006 standards evaluation [3]. In addition the ENDF/B-VIII.0 release split the natural carbon cross sections into the isotopes¹²C,¹³C, and¹⁴C for the first time. These details call for the re-measurement of the¹³C cross sections in sensitive regions. Ten elastic scattering angular distributions were recently measured for incident neutron energies between 0.5 and 3.25 MeV at the University of Kentucky Accelerator Laboratory (www.pa.uky.edu/accelerator/) using nanosecond pulsed beams and time-of-flight techniques. An overview of neutron production and detection, the new digital data acquisition system, and data analysis will be presented. Results are compared with data from previous measurements and database evaluations. 

γ-ray production cross sections have been deduced for reactions with incident neutrons having energies from 1.5 - 4.7 MeV. Similar measurements were made on a natural Ti sample to establish an absolute normalization. The resulting γ-ray production cross sections are compared to TENDL and TALYS calculations, as well as data from previous measurements. The models are found to describe the production cross sections for mostγrays observed from⁵⁴Mn and⁵⁴Fe rather well. 

The low-lying structure of⁷⁴Ge has been studied with γ-ray detection following inelastic neutron scattering. From excitation function and angular distribution data, the levels and transitions have been characterized including level spins and lifetimes, branching ratios, and multipole mixing ratios. In addition, a number of levels found in the literature for⁷⁴Ge appear to be erroneously placed. Upon removal of these states from the level scheme, excellent agreement with large-scale shell-model calculations was obtained.