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DOE OSTI · 3005746

Benchmarking a Defeatured Geant4 NIF Model with HTOAD and HNED Neutron Data

He, Eric [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Yeamans, Charles [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]
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Abstract

This study benchmarks a simplified Geant4 NIF Target Chamber (TC) model against foil measurements in two instruments: the HTOAD and HNED Snout. The number of product atoms per source neutron per gram ( N 0 /n/g ) is compared across multiple locations and material configurations. The model reproduces high energy threshold reactions dominated by 14 MeV neutrons to within a few percent, depending on location. Discrepancies occur where scattering and moderation are significant for low energy threshold reactions. The defeatured Geant4 model achieves comparable statistical precision with ∼400 times less CPU time than a full fidelity TC model in MCNP. The results can be produced locally on a laptop without the need for high performance computing. Low energy biasing can be improved by preserving room return pathways and implementing IRDFF cross section evaluations.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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BibTeXRIS

He, Eric [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Yeamans, Charles [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]. 2025-12-02. Benchmarking a Defeatured Geant4 NIF Model with HTOAD and HNED Neutron Data. https://doi.org/10.2172/3005746

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