NNDC

The National Nuclear Data Center (NNDC) is a United States national facility at Brookhaven National Laboratory that collects, evaluates, and disseminates nuclear science data used in research and applications. It operates under the U.S. Department of Energy and serves as a central resource for nuclear structure information, decay data, and reaction cross sections, supporting researchers, educators, and industry.

NNDC maintains several major data libraries and tools, including the Evaluated Nuclear Structure Data File (ENSDF), the experimental nuclear structure data compilation XUNDL, the Nuclear Data for Utilities (NUDAT) database, and the Nuclear Science References (NSR) bibliographic index. It also provides user-facing resources such as the Chart of Nuclides, the Nuclear Wallet Cards, and the Z-A Chart, which present nuclide properties and relationships in accessible formats.

In addition to data curation, NNDC publishes core reference works such as Nuclear Data Sheets and Nuclear Data Tables, which assemble evaluated data for individual nuclides and are widely used in research, engineering, and education. The center’s data underpin applications in basic nuclear physics, reactor design and safety, medical isotope production, astrophysical modeling, and radiation protection.

NNDC participates in international collaboration through the International Nuclear Data Centers Network coordinated by IAEA and works with other national laboratories and universities to advance data standards, interoperability, and open access. The NNDC website provides comprehensive access to databases, tools, documentation, and tutorials.