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DOE OSTI · 2570754

Design of a High-Assay Low-Enriched Uranium Tri-Structural Isotropic Critical Experiment for Advanced Reactor Validation

Trellue, Holly Renee [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000320510852)·Cutler, Theresa Elizabeth [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Luther, Erik Paul [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Wynne, Nicholas Alan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Lee, Justin Lawrence [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Downey, John Norlin [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Stinson, Scott William [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Stolte, Kristin Nichole [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Sanchez, Rene [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Maldonado, Alexis [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Morbach, Hannah Pauline [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]
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Abstract

High-assay low-enriched uranium (HALEU) fuel is a key component of many small modular reactor designs. Critical experiments are an important way to understand the neutronic performance of systems by obtaining nuclear data validations through measurements. Data reduce uncertainty and risk by showing that systems respond as predicted to changes such as temperature, subsequently advancing the overall technology readiness level of the materials within. Numerous critical experiments have been performed at the National Criticality Experiments Research Center (NCERC) operated by Los Alamos National Laboratory at the Nevada National Security Site since it became operational in 2011. However, the first experiment with HALEU fuel did not occur until 2024. Through extensive engineering, the experiment described in this paper was successfully designed and executed for the Comet vertical lift assembly at NCERC to perform measurements with HALEU tri-structural isotropic fuel that will assist in validation of nuclear data and computational modeling of small modular reactors for years to come.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSDeimos critical experimentHigh-assay low-enriched uraniumTRISOnuclear data

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Trellue, Holly Renee [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000320510852), Cutler, Theresa Elizabeth [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Luther, Erik Paul [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Wynne, Nicholas Alan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Lee, Justin Lawrence [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Downey, John Norlin [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Stinson, Scott William [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Stolte, Kristin Nichole [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Sanchez, Rene [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Maldonado, Alexis [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Morbach, Hannah Pauline [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]. 2025-06-18. Design of a High-Assay Low-Enriched Uranium Tri-Structural Isotropic Critical Experiment for Advanced Reactor Validation. https://doi.org/10.1080/00295450.2025.2504149

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