Space and energy dependent neutron slowing down time in graphite

Autor: Gibbons, Francis W.
Rok vydání: 1967
Druh dokumentu: Diplomová práce
Popis: This thesis document was issued under the authority of another institution, not NPS. At the time it was written, a copy was added to the NPS Library collection for reasons not now known. It has been included in the digital archive for its historical value to NPS. Not believed to be a CIVINS (Civilian Institutions) title.
A 4 foot cube, graphite moderating assembly was con­structed at the M.I.T. Rockefeller Van de Graaff accelerator. Using the pulsed neutron experimental installation, a neutron burst of 200 nsec width was injected into the center of the assembly. Prompt gamma radiation from a neutron resonance capture by an indicator foil in the moderator was measured with a 3 inch x 3 inch sodium iodide scintillation detector, as a function of time after the neu­tron pulse. The energy dependence of slowing down time was experimentally measured by using resonance absorber foils of cadmium, indium, and gold with isolated resonances of 0.2, 1.46 and 5.0 eV respectively. By varying the distance of the foil from the source, the spatial dependence of slowing down time was also investigated. Comparisons are made with slowing down theory. The experimental results, together with their estimated uncertainties are tabulated. (Original abstract includes table of results unable to replicate here)
Databáze: Networked Digital Library of Theses & Dissertations