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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.
Mo-Chen Hsu
Nuclear Technology | Volume 79 | Number 3 | December 1987 | Pages 274-283
Technical Paper | Fission Reactor | doi.org/10.13182/NT87-A34017
Articles are hosted by Taylor and Francis Online.
The time series modeling approach is introduced to estimate the prompt-neutron decay constant. Neutron flux noise data of three fuel cycles of a high flux isotope reactor are analyzed. The noise data detected from an ionization chamber outside the reactor core surrounded by a beryllium reflector were recorded at full-power operation. The decay constant corresponding to a rounded-off corner break frequency can be estimated from the characteristic roots of adequate autoregressive moving average models. This implicit characteristic identification is one of the advantages of off-line modeling analysis. The estimated neutron lifetime in the beginning of fuel cycle is 38 µs (expected value = 35 µs). The estimated lifetime near the end of cycle is 66 µs (expected value = 70 µs).