Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed on Mar. 13, 2007). PDF text: xiii, 125 p. : ill. (some col.) UMI publication number: AAT 3221254. Includes bibliographical references. Also available in microfilm, microfiche and paper format.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed February 25, 2010). PDF text: xii, 92 p. : col. ill. ; 29 Mb. UMI publication number: AAT 3386942. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references (leaves 99-101).

Thesis (M.S.)--Brigham Young University. Dept. of Physics and Astronomy, 2005. / Includes bibliographical references (p. 68-70).

Call number: LD2668 .T4 1961 N37

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 196-200).

Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

This work focuses on using forward and adjoint transport in a hybrid application of 3-D deterministic (PENTRAN) and Monte Carlo (MCNP5) codes to model a series of neutron detector blocks. These blocks, or “channels,” contain a unique set of moderators with 4 atm He-3 proportional detectors tuned to detect and profile a gross energy spectrum of a passing neutron (SNM) source. Ganging the units together as a large area system enables one to apply time gating the source-detector response to maximize signal to noise responses from a passing source with minimal background; multiple units may be positioned as a collective synthetic aperture detector array to be used as a way of performing real time neutron spectroscopy for detecting special nuclear materials in moving vehicles.

In this work novel solid-state neutron detectors based on Gallium Nitride (GaN) have been produced and characterized. GaN is a radiation hard semiconductor which is commonly used in commercial optoelectronic devices. The important design consideration for producing GaN-based neutron detectors have been examined, and device simulations performed. Scintillators and p-i-n diode-type neutron detectors have been grown by metalorganic chemical vapor deposition (MOCVD) and characterized. GaN was found to be intrinsically neutron sensitive through the Nitrogen-14 (n, p) reaction. Neutron conversion layers which produce secondary ionizing radiation were also produced and evaluated. GaN scintillator response was found to scale highly linearly with nuclear reactor power, indicating that GaN-based detectors are suitable for use in the nuclear power industry. This work is the first demonstration of using GaN for neutron detection. This is a novel application for a mature semiconductor material. The results presented here provide a proof-of-concept for solid-state GaN-based neutron detectors which offer many potential advantages over the current state-of-the-art, including lower cost, lower power operation, and mechanical robustness. At present Helium-3 proportional counters are the preferred technology for neutron detection, however this isotope is extremely rare, and there is a global shortage. Meanwhile demand for neutron detectors from the nuclear power, particle physics, and homeland security sectors requires development of novel neutron detectors which are which are functional, cost-effective, and deployable.