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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.
Yasushi Nomura, Yoshitaka Naito
Nuclear Technology | Volume 121 | Number 1 | January 1998 | Pages 3-13
Technical Paper | Kiyose Birthday Anniversary | doi.org/10.13182/NT98-A2814
Articles are hosted by Taylor and Francis Online.
Scenario identification, preparation of reliability data, and fault-tree construction were conducted for a criticality in a pulsed column of a typical model of a reprocessing facility to find a weak link in the system. The plant system data, the basic reliability data with the fault-tree analysis code FTL, were supplied from NUKEM GmbH, Germany. In this exercise, a low nitric acid concentration in the scrub flow to the pulsed column is initiated by failures of the reagent preparation system of the primary separation cycle, triggering plutonium accumulation, eventually exceeding the safety limit of the scrub column, and thus a criticality accident occurs. The occurrence frequency was evaluated to be 2.2 × 10-5/yr for this most conservative case of the accident scenario. The main contributor was investigated by the fault-tree branch analysis and identified to be human error relating to the sampling measurement for fresh nitric acid scrub feed. Because 2.2 × 10-5/yr is quite a high value in comparison with the generally accepted 10-6/yr, Monte Carlo uncertainty analysis assuming an error factor of 5 for each of the reliability data was conducted to predict a 90% confidence range of 1.9 × 10-6/yr to 8.25 × 10-5/yr. In addition, there might be unforeseen equipment failures related to the same criticality scenario. The additional analysis and discussion lead to the recommendation to adopt shape and dimension control in the design stage for the whole range of plutonium concentrations from a criticality safety point of view.
