Nuclear reactions are useful tools to study the structure of the atomic nucleus. One of the most popular reactions over the last several decades is the transfer reaction, and the advent of rare isotope beam facilities has opened up new swaths of the nuclear chart available for exploration with this technique. In principle, different techniques should give consistent nuclear structure information (like the spectroscopic factor which quantifies single-particle occupancy) for a given isotope. However there is a well-established discrepancy between spectroscopic factors extracted from transfer reaction data and those extracted from knockout reaction data. In particular, reduction factors (ratios of extracted spectroscopic factors to theoretical expectation) from knockout data show a strong dependence on nuclear asymmetry, whereas the transfer measurements show at most a weak dependence. This discrepancy not only raises important questions on the influence of nucleon-nucleon correlations in nuclear structure, but also calls into question the validity of the relevant nuclear reaction techniques.This dissertation describes the measurement of the $^{34}$Ar$(p,d)^{33}$Ar and $^{46}$Ar$(p,d)^{45}$Ar single-neutron transfer reactions at 70 MeV/u. The motivation of this study is to measure the same transfer reactions on argon examined in earlier work at low energy, while matching the high beam energy of previous knockout measurements on argon. Raising the beam energy to a regime where few reliable measurements exist could illuminate potential defects in the transfer reaction mechanism. We performed a kinematically complete measurement of the differential cross sections for these $(p,d)$ reactions at the National Superconducting Cyclotron Laboratory using several detector systems. The High Resolution Array (HiRA) detected the outgoing deuterons, the S800 Spectrograph detected the heavy argon recoil, and two Microchannel Plates (MCPs) tracked the incoming beam to normalize the cross section and to better localize the transfer on the reaction target. We carried out various calibrations on each individual detector system (including a detailed characterization of silicon detectors in HiRA) before merging and normalizing the data to generate the cross sections of interest.We extracted spectroscopic factors using the adiabatic distorted wave approximation (ADWA) framework implemented in the TWOFNR code. Both the CH89 global optical potential as well as the microscopic Jeukenne, Lejeune, and Mahaux (JLM) optical potential produced spectroscopic factors for each reaction system. The resulting reduction factors corroborate the low-energy results and disagree with the knockout data by showing a weak asymmetry dependence between the neutron-rich $^{46}$Ar and the proton-rich $^{34}$Ar. Therefore, the transfer reaction mechanism yields consistent results even at a high beam energy. We advocate for further transfer reaction measurements at high asymmetry, as well as a deeper theoretical understanding of both the transfer and knockout reaction mechanisms.
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