One important overarching goal in nuclear science is the experimental investigation of nuclear structure. Understanding how the structure of the nucleus evolves as more neutrons (N) and protons (Z) are added is vital to probing the mechanisms that drive the evolution of shell structure. One tool to investigate the migration of energy levels along isotopic chains is through the characterization of isomeric states. Isomeric states can signal a transition between very different nuclear configurations and therefore can be an important test of the evolution of nuclear structure. β-decay spectroscopy is used to provide a wealth of information on exotic isotopes including half-lives, branching ratios, and energy levels. The selectivity provided by decay spectroscopy places constraints on the spins and parities of nuclear levels. Recently a new planar Germanium Double-Sided Strip detector (GeDSSD) has been used in decay spectroscopy experiments at the National Superconducting Cyclotron Laboratory (NSCL). Exotic ions are produced, delivered to, and stopped within the GeDSSD, where the β-decay electrons, conversion electrons and γ rays are detected. In the present work, the electron and γ ray detection efficiencies of the GeDSSD were determined with source measurements and the performance of the GeDSSD with radioactive ions was characterized in multiple experiments and included β-decay correlation efficiencies, β-γ summing corrections, and charge state separation through Total Kinetic Energy (TKE) measurements. Following the development of the GeDSSD, it was applied here to the A~110 region to explore low-energy isomeric states. Nuclei in this region have had indications of changing nuclear shapes as a function of nucleon number for many years, and much theoretical work has been done in an attempt to explain the existing experimental data. The theoretical calculations predict a changes in structure as a function of nucleon number, and data is needed to clarify the understanding of the region. The search for isomeric states is one method by which the nuclear structure of the region can be clarified. Measuring conversion coefficients of nuclear transitions can constrain the multipolarity of the isomeric transition, which in turn can constrain the spins and parities of the initial and final states. In order to address this need for data, a recent NSCL β-decay experiment focused on several A~110 nuclei with Z ranging from 41 to 46 and the results are presented here. In particular, this work discusses an isomeric state in 115Ru at 123.8 keV, which was previously placed at an unknown energy. This isomeric state is one of several isomers in the Ru and Pd isotopic chains, likely arising from the h11/2 orbital. Additionally, several short-lived (less than 20 mus) isomeric states in 118Ag, 107Mo, and 109Mo are discussed.
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