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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Tyler Sumner, Tingzhou Fei
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S309-S322
Technical Paper | doi.org/10.1080/00295639.2021.2009982
Articles are hosted by Taylor and Francis Online.
The Versatile Test Reactor (VTR) is a fast spectrum test reactor currently being developed in the United States under the direction of the U.S. Department of Energy, Office of Nuclear Energy. Safety analysis of the conceptual VTR design is being performed using the SAS4A/SASSYS-1 fast reactor safety analysis code with a model representing the reactor core, primary and intermediate heat transport systems, reactor vessel auxiliary cooling system, and reactor protection system. The system’s response and safety performance has been evaluated for a wide spectrum of event initiators and accident sequences. This paper focuses on the results for several unprotected transient scenarios where the reactor protection system is assumed to fail to take any action. Even without the reactor protection system, the strong reactivity feedback response of the core reduces power to safe levels matching the available heat rejection. In the station blackout transient, the primary heat transport system is able to transition quickly and effectively to natural circulation. At the current stage of design, transient simulation results for the VTR indicate that large safety margins exist for many event initiators, including the unprotected transients presented in this paper.