One of the prevalent questions in nuclear science is the origin of the elements. There are two stellar nucleosynthesis processes considered to be responsible for the production of the majority of the abundances of the elements heavier than iron; the slow neutron-capture process (s-process) and the rapid neutron-capture process (r-process). Both of these processes are characterized by the successive capture of neutrons on nuclei, with the major differences between the processes being the timescale over which the processes occur and the host environment. The s-process occurs in low neutron-density environments, such as low- to intermediate-mass stars, and proceeds slowly along the valley of stability. Since the nuclei involved are close to stability, the reactions involved are amenable to direct measurements. The r-process progresses through an explosive event with high neutron densities which drives material far from stability. The recent observation of a neutron star merger event by LIGO and Virgo and the subsequent electromagnetic follow up has demonstrated that an r-process event can occur in these rare events, but it has not ruled out other potential astrophysical sites. To better understand and model the r-process, several nuclear properties are needed for a large number of nuclei, including neutron-capture cross sections. R-process nuclei are not viable for direct measurement of neutron-capture cross sections since the nuclei involved are far from stability, and thus have short half-lives. Therefore, several indirect measurement techniques have been developed to provide experimental constraints on neutron-capture cross sections. One such method is the beta-Oslo method, which uses beta decay to populate highly excited states of a nucleus. The resulting de-excitation via the emission of gamma rays is used to extract statistical nuclear properties of the daughter nucleus. These properties are then used as input in a reaction model to constrain the neutron-capture cross section. The beta-Oslo method can provide a large number of constrained neutron-capture cross sections far from stability, but it is necessary to validate the method using a direct neutron capture measurement. This work will present a validation of the beta-Oslo method in the A = 80 mass region with the 82Se(n, gamma)83Se reaction. The nuclide 83Se can be accessed through the beta-decay of 83As, which was studied at the National Superconducting Cyclotron Laboratory with the total absorption spectrometer, SuN. Using the beta-Oslo method, the cross section of the 82Se(n, gamma)83Se reaction was constrained. A direct measurement of the 82Se(n, gamma)83Se reaction was performed with the Detector for Advanced Neutron Capture Experiments and the cross section obtained from the direct measurement is compared to the cross section determined using the beta-Oslo method. The results are in good agreement, validating the beta-Oslo method as a viable method for constraining neutron-capture cross sections.
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