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DOE OSTI · 3029849

A new database website for nuclear level densities

Rathi, Chirag [Ohio University, Athens, OH (United States)] (ORCID:0009000471496442)·Voinov, Alexander [Ohio University, Athens, OH (United States)] (ORCID:0000000159187672)·Godbey, Kyle [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000306223646)·Meisel, Zach [Air Force Institute of Technology, OH (United States)] (ORCID:0000000284038879)·Leibensperger, Kristen [Ohio University, Athens, OH (United States); University of California, Davis, CA (United States)] (ORCID:0000000294158436)
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Abstract

We introduce a new open-access, web-based database (http://nld.ascsn.net), Current Archive of Nuclear Density of Levels (CANDL), that hosts experimental nuclear level density (NLD) datasets from a variety of techniques and energy ranges. Built using the Dash framework in Python, the database is designed to be interactive and user-friendly, allowing researchers to search, visualize, fit, and export NLD data with minimal effort. This resource includes data extracted from evaporation spectra, Oslo method variants, and other experimental techniques that cover excitation energies beyond the neutron resonance region. The database supports on-the-fly fitting with two widely-used phenomenological models—the Constant Temperature (CT) model and the Back-Shifted Fermi Gas (BSFG) model—selected for their simplicity and computational efficiency. Future versions aim to include additional datasets and model types, as well as easy-to-use interfaces to data science techniques. Here, this platform offers a vital tool for the nuclear physics, astrophysics, medicine, and reactor design communities.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGNuclear level densityPhenomenological modelsPython dashWeb database

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Rathi, Chirag [Ohio University, Athens, OH (United States)] (ORCID:0009000471496442), Voinov, Alexander [Ohio University, Athens, OH (United States)] (ORCID:0000000159187672), Godbey, Kyle [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000306223646), Meisel, Zach [Air Force Institute of Technology, OH (United States)] (ORCID:0000000284038879), Leibensperger, Kristen [Ohio University, Athens, OH (United States); University of California, Davis, CA (United States)] (ORCID:0000000294158436). 2025-12-30. A new database website for nuclear level densities. https://doi.org/10.1016/j.cpc.2025.110018

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