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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Lightbridge announces first U-Zr fuel rod samples extruded at INL
Lightbridge Corporation announced today that it has reached “a critical milestone” in the development of its extruded solid fuel technology. Coupon samples using an alloy of zirconium and depleted uranium—not the high-assay low-enriched uranium (HALEU) that Lightbridge plans to use to manufacture its fuel for the commercial market—were extruded at Idaho National Laboratory’s Materials and Fuels Complex.
Brian R. Nease, Taro Ueki
Nuclear Science and Engineering | Volume 157 | Number 1 | September 2007 | Pages 51-64
Technical Paper | doi.org/10.13182/NSE07-A2712
Articles are hosted by Taylor and Francis Online.
A coarse-mesh projection method has been developed for the Monte Carlo calculation of dominant eigenvalue ratio [dominance ratio (DR)]. The first step of the method consists of the regression analysis of the multivariate time series from the coarse-mesh binning of the Monte Carlo fission source distribution. The second step is computation of the eigenvectors of the adjoint matrix of noise propagation. In general, projections on these eigenvectors can be utilized to compute important characteristics of the eigenmodes of fission source distribution. In this work, it has been proven that if the eigenvector corresponding to the largest eigenvalue of the aforementioned adjoint matrix is taken to be the vector for projection, the projected scalar time series follows the autoregressive process of order one with the root of characteristic polynomial, i.e., the autocorrelation coefficient, being the DR of fission source distribution. Numerical results are presented for four problems including one-energy-group checkerboard-type problems, a one-energy-group cube problem and a continuous-energy pressurized water reactor core problem. The strength of the method is twofold; (a) the elimination of the use of autoregressive moving average fitting, and (b) no need to optimize the order of fitting.