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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.
C. R. Weisbin, E. M. Oblow, J. H. Marable, R. W. Peelle, J. L. Lucius
Nuclear Science and Engineering | Volume 66 | Number 3 | June 1978 | Pages 307-333
Technical Paper | doi.org/10.13182/NSE78-3
Articles are hosted by Taylor and Francis Online.
This paper presents the first results of a comprehensive application of the sensitivity theory developed for the FORSS code system to the analysis of fast reactor integral experiments. A variety of assemblies and performance parameters were studied to determine the nuclear data sensitivity as a function of nuclide, reaction type, and energy. Comprehensive libraries of energy-dependent sensitivity coefficients were developed in a computer retrievable format for several critical assemblies. Uncertainties induced by nuclear data were quantified using preliminary energy-dependent relative covariance matrices evaluated with ENDF/B-IV cross sections and processed for 238U(n,f), 238U(n,γ), 239Pu(n,f), 239Pu(n,γ), and . Calculational results, cross-section covariances, and integral results and their covariances were used in a consistent fashion to improve uncertainty estimates of fast reactor core performance. A first attempt was made to quantify specifications for new cross-section measurements required to satisfy specific design goals at minimum experimental cost. An analysis of several critical experiments indicated that design accuracy goals of 0.5% in k and 2% in the central 238U capture: 239Pu fission ratio (28c/49f) ratio in mixed oxide liquid-metal fast breeder reactor cores are unlikely to be attained in the near future. This assumes that the nuclear data are based only on microscopic measurements, and the current cross-section measurement program is not changed dramatically. Current estimates are 2.3% in k and 7.3% in central reaction ratio using only differential covariance information. Using the measurements in ZPR-6/7 for k and central 28c/49f in a cross-section adjustment scheme with assigned uncorrected standard deviations of 1 and 2%, respectively, standard deviations of the same parameters were computed to be 0.7 and 1.8%. Results of integral experiments, therefore, are needed to improve uncertainty estimates of reactor performance for current fast reactor design work.
