Indirect reaction methods play an important role in probing many astrophysical nucleosynthetic processes in cases where a direct measurement in the laboratory is technically challenging or not possible. However, the resulting astrophysical data is only as good as the quality of the reaction theories used to extract it from experimental measurements. In this thesis we explore two indirect reaction methods, transfer and charge-exchange reactions, with an emphasis on the reaction theory models used to interpret the measurement.Deuteron induced transfer reactions are a useful tool for probing single particle capture reactions. We discuss a methodology that has been developed to extract spectroscopic factors from transfer to low lying resonances. Spectroscopic factors are used to experimentally constrain the astrophysical reaction rate of interest via the resonance strength. Here, we present results of three transfer reaction studies: 30P(d,n) to extract the 30P(p,γ) reaction in classical novae, 23Al(d,n) to extract the 23Al(p,γ) reaction in type-I x-ray bursts, and 56Ni(d,n) to extract the 56Ni(p,γ) reaction, also important in x-ray bursts. In all of these cases, the transfer data was able to reduce the uncertainty in the astrophysical reaction rate and this marks the first experimental constraints on the 30P(p,γ) reaction rate.Charge-exchange reactions have diverse applications to astrophysical processes, ranging from constraining electron capture rates in core collapse supernovae, to probing the nuclear symmetry energy, important to understanding neutron stars and their mergers. However, the reactions models which describe charge-exchange reactions remain relatively underdevelopedcompared to those used to describe other reactions. In this thesis we present an initial study exploring several aspects of charge-exchange reaction models.We conduct a systematic study of charge-exchange transitions to 0+ isobaric analog states over a range of targets and beam energies using the distorted wave Born approximation. We use a two-body framework, which is characterized by a nucleon-target Lane potential, and a three-body framework, which uses an NN interaction to describe charge-exchange between a scattering nucleon and a valence nucleon bound to an inert core. We explore the impact of different interactions, varying both the potential which mediates the charge-exchange and the interaction which describes the incoming and outgoing distorted waves.We find that the two-body formalism was better able to describe both the shape and magnitude of charge-exchange data, capturing 31% of the data within the error band created by normalized calculations using two different optical potentials. This is opposed to describing less that 15% of the data in the three-body model. Although there was a 50% difference, on average, between the charge-exchange cross sections produced using Koning-Delaroche and Chapel-Hill parameter sets, neither parameter set is preferred by the data.The shape of the angular distributions produced by the three-body framework differ significantly from their two-body counterparts and from experimental data. We determined that this difference arises from a selection of different partial waves between the formalisms. The Lane interaction in the two-body framework selects lower partial waves, indicating a more central interaction, while the Gogny and AV8’ interactions select higher partial waves, resulting in a reaction located near the surface of the target where the active nucleons are in close proximity. Overall, the charge-exchange cross section is very sensitive to the choice of interaction, indicating that charge-exchange could be a useful tool to further constrain nuclear interactions.
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