<p>Nearly mono-energetic, high intensity (~10<super>7</super> gamma/s), and approximately 100% linearly polarized gamma-ray beams at energies between 5.15 and 7.60 MeV were used to induce photofission of <super>232</super>Th, <super>233,235,238</super>U, <super>237</super>Np, and <super>239,240</super>Pu. Prompt fission neutron yields parallel and perpendicular to the plane of beam polarization were measured using arrays of 12-18 liquid scintillator detectors. Prompt neutron polarization asymmetries close to zero were found for the even-odd actinides (<super>233,235</super>U, <super>237</super>Np, and <super>239</super>Pu), while significant asymmetries were found for the even-even actinides (<super>232</super>Th, <super>238</super>U, and <super>240</super>Pu). Predictions based on previously measured fission fragment angular distributions combined with a model of prompt neutron emission agree well with our experimental results. Finally, we describe a new method of measuring the enrichment of special nuclear material based on our results.</p> / Dissertation

abstract: The nucleon resonance spectrum consists of many overlapping excitations. Polarization observables are an important tool for understanding and clarifying these spectra. While there is a large data base of differential cross sections for the process, very few data exist for polarization observables. A program of double polarization experiments has been conducted at Jefferson Lab using a tagged polarized photon beam and a frozen spin polarized target (FROST). The results presented here were taken during the first running period of FROST using the CLAS detector at Jefferson Lab with photon energies ranging from 329 MeV to 2.35 GeV. Data are presented for the E polarization observable for eta meson photoproduction on the proton from threshold (W=1500 MeV) to W=1900 MeV. Comparisons to the partial wave analyses of SAID and Bonn-Gatchina along with the isobar analysis of eta-MAID are made. These results will help distinguish between current theoretical predictions and refine future theories. / Dissertation/Thesis / Ph.D. Physics 2011

abstract: A series of experiments using a polarized beam incident on a polarized frozen spin target (FROST) was conducted at Jefferson Lab in 2010. Results presented here were taken during the second running period with the FROST target using the CEBAF Large Acceptance Spectrometer (CLAS) detector at Jefferson Lab, which used transversely-polarized protons in a butanol target and a circularly-polarized incident tagged photon beam with energies between 0.62 and 2.93 GeV. Data are presented for the F and T polarization observables for h meson photoproduction on the proton from W = 1.55 GeV to 1.80 GeV. The data presented here will improve the world database and refine theoretical approaches of nucleon structure. / Dissertation/Thesis / Doctoral Dissertation Physics 2016

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