Engineering Commons^™

Determining 235u Enrichment Using A Dual-Energy Approach For Delayed Neutron Measurements, Angela Lynn Lousteau

Doctoral Dissertations

Bulk uranium items are often measured using active neutron interrogation systems to take advantage of the relatively high penetrability of neutrons, providing the ability to quickly and accurately measure uranium masses in large, dense configurations. Active techniques employ an external neutron source to induce fission in the uranium and subsequently measure emitted prompt fission or delayed neutrons. Unfortunately, the emitted neutrons from ²³⁵U [uranium-235] and ²³⁸U [uranium-238] are, for all practical purposes, indistinguishable; therefore, commonly used systems such as the Active Well Coincidence Counter, the ²⁵²Cf [californium-252] Shuffler, and other systems based on measurement of prompt or …

An Optimization Method For Matched Abundance-Ratio Cascades By Varying The Key Weight, Richard Dale Harvey

Doctoral Dissertations

The theory of multicomponent isotope separation in matched abundance-ratio cascades (MARC) has been well established by Cohen, de la Garza, von Halle, and others. Because separation factors of different isotopes vary in the same separator, isotopic weight fractions cannot be matched in the same sense as in a two-component ideal system. Therefore, the abundance ratios of the desired isotope and a selected key isotope are matched, hence the name. These ratios are matched by choosing a key weight between the two selected components of separation.

Desirable stable isotopes for separation can exist as minor components of a natural, multicomponent isotope …