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DOE OSTI · 3005575

GEANT3 simulations for a beryllium Moderator for the Neutron Target Demonstrator (NTD)

Dellmann, Sophia Florence [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000026348858X)·Reifarth, René [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000238555816)·Cooper, Andrew Leland [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000234941672)·Couture, Aaron Joseph [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000208613616)·Harrington, Caroline [Air Force Institute of Technology, Wright-Patterson AFB, OH (United States)]·Knapova, Ingrid [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000347710328)
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Abstract

Measurements of neutron-induced reactions, particularly on short-lived nuclei, are crucial for nuclear astrophysics and applications. The Neutron Target Demonstrator (NTD) aims to address this by using a strong mod erated spallation neutron source coupled with an ion storage ring. This work investigates the potential of improving the neutron moderator, a key component of the NTD. Using GEANT3 simulations, we compare the performance of the existing 80 cm carbon moderator with a new moder ator design, which utilizes beryllium pieces available at LANL to form a core surrounded by carbon. Simulations were performed 800 MeV pro tons incident on a tungsten target. The results demonstrate that the beryllium-core moderator increases the density of moderated neutrons within the central beam pipe by roughly a factor 4 compared to the pure carbon moderator. This enhancement makes the beryllium-core design a very promising option for future experiments focused on neutron-induced measurements in inverse kinematics.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Dellmann, Sophia Florence [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000026348858X), Reifarth, René [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000238555816), Cooper, Andrew Leland [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000234941672), Couture, Aaron Joseph [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000208613616), Harrington, Caroline [Air Force Institute of Technology, Wright-Patterson AFB, OH (United States)], Knapova, Ingrid [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000347710328). 2025-11-20. GEANT3 simulations for a beryllium Moderator for the Neutron Target Demonstrator (NTD). https://doi.org/10.2172/3005575

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