Author ORCID Identifier
Year of Publication
Doctor of Philosophy (PhD)
Arts and Sciences
Physics and Astronomy
Dr. Bradley R. Plaster
Dr. William Michael Snow
One of the most outstanding questions in physics is the matter-antimatter asymmetry of the Universe, resulting from excess baryogenesis processes during the early moments of the formation of the Universe. At present, the types of processes needed to explain this matter excess, so-called `CP-violating processes' are known to exist within the present framework of the Standard Model of particle physics. However, decades of research has shown that our understanding of the origin of these processes is incomplete, as we do not presently know of enough sources of CP-violating processes to account for the large baryon asymmetry that we observe. The Neutron Optics Time Reversal EXperiment (NOPTREX) collaboration was formed to investigate the existence of possible CP-violating processes in compound neutron-nuclear resonance scattering reactions in which large parity-violating effects are observed. One of the most crucial elements of the NOPTREX experiments is defining the optimal nuclear scattering target material. This work centers on the characterization of the most promising candidate nucleus for such an investigation, 139La; in particular, we focus on the experimental efforts to measure the longitudinal parity violation present in the 0.734 eV neutron resonance that took place at Flight Path 12 at the Los Alamos Neutron Science Center (LANSCE) from 2017-2020.
Digital Object Identifier (DOI)
This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-SC0014622 from 2018-2021.
This work was supported by the National Science Foundation Graduate Research Fellowship Program (NSF GRFP), Award Number 1247392, from 2016-2019.
Schaper, Danielle, "Neutron Spectroscopy of the Parity-Violating 0.734 eV Neutron Resonance in Lanthanum-139 in Preparation for the NOPTREX Time Reversal Violation Experiment" (2022). Theses and Dissertations--Physics and Astronomy. 91.