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Division Spotlight
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.
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.
Phiphat Phruksarojanakun, Paul P. H. Wilson
Nuclear Science and Engineering | Volume 156 | Number 2 | June 2007 | Pages 164-179
Technical Paper | doi.org/10.13182/NSE07-A2694
Articles are hosted by Taylor and Francis Online.
Three variance reduction techniques for the ongoing development of Monte Carlo isotopic inventory analysis are implemented as alternatives to improve the precision of Monte Carlo simulations. The Forced Reaction technique is designed to force an atom to undergo a predefined number of reactions in a given control volume. Biased Reaction Branching is primarily focused on improving statistical results of the isotopes that are produced from rare reaction pathways. Biased Source Sampling is aimed at increasing frequencies of sampling rare initial isotopes as the starting Monte Carlo particles. A variety of test problems is uniquely designed to demonstrate the validity and the improvement, relative to the analog problem, of each technique. The increases in precision due to the variance reduction techniques usually come at the expense of longer computing times per history.A figure of merit (FOM) is developed as a tool to monitor the efficiency of Monte Carlo simulations with variance reduction schemes. A number of statistical characteristics of Monte Carlo isotopic inventory calculations are used to construct a variety of FOM formulations. Two of them offer robust FOMs: one based on the relative error of a known target isotope (1/R2T) and one based on the overall detection limit corrected by the relative error (1/DkR2T).Figures of merit are later used to quantitatively assess the efficiencies of Monte Carlo simulations under different scopes of interest. Given a defined set of variance reduction parameters to produce desired effects, the efficiency measurements from an FOM agree with the expected performance.
