Speaker
Description
The National Nuclear Data Center (NNDC) provides access to physics research data through a collection of 40 websites. Each is dedicated to a topic, a database, or to a previous conference. Many also have long histories, with the oldest websites having been deployed in 1998. Collectively, these websites receive millions of requests for data, with an estimated 5.2 million retrievals in 2020 alone. The popularity of the NNDC’s most prominent websites can attest to both its reach and its impact.
The Evaluated Nuclear Structure Data File (ENSDF) format has its own dedicated database and a website of the same name. The ENSDF website provides evaluated research data on excitation states for all known nuclides, in addition to data on nuclear reactions and decay. In 2020, the ENSDF website received its own chart interface to enable visual exploration of the ENSDF database.
ENSDF is the second most-visited website after NuDat, which maintains the original Chart of Nuclides. This interface visualizes patterns in half-lives, decay energies, fission yields, and more by mapping each nuclide onto a coordinate grid. In addition to the Chart of Nuclides, NuDat provides several plotting tools, all of which received updates in 2019. Of particular note is the Advanced Cross-Variable Plot, which graphs relationships between observable nuclear properties. In 2021, the NuDat 3.0 beta was released as a preview of a faster, smoother Chart of Nuclides.
To address the needs of specific users, the NNDC website also provides tools which query and visualize subsets of the main libraries for specific applications. The Medical Isotope Radiation Dose (MIRD) format is designed for isotopes used in nuclear medicine, and has its own dedicated website. The process of thermal neutron capture decay is also recorded in the CapGam website. In 2020, the MIRD website was updated to improve response times and add nuclear decay diagrams. Shortly afterwards, CapGam was redesigned with responsive user interfaces and a streamlined update process to keep up with new evaluations.
More recently, the NNDC has turned its attention towards modernizing its web services. Over time, the differences in each website’s creation and purpose have complicated updating code and correcting programming errors. The NNDC’s most recent web development project was started to create a standardized development process for present and future NNDC websites. It started with using Git version control for organizing and managing changes to code. It then progressed to using the Gradle build tool to make updates simpler and faster. The final (and still ongoing) step in this project is to re-deploy each website as a portable Web Archive (WAR) file. Each of these steps was taken with the intent of streamlining NNDC web development, which in turn will hopefully improve existing websites and guide the creation of new ones.
Work sponsored by the Office of Nuclear Physics, Office of Science of the U.S. Department of Energy, under Contract No. DE-AC02-98CH10886.