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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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Elad Steinberg, Shay I. Heizler
Nuclear Science and Engineering | Volume 197 | Number 9 | September 2023 | Pages 2343-2355
Research Article | doi.org/10.1080/00295639.2023.2190728
Articles are hosted by Taylor and Francis Online.
This work generalizes the discrete implicit Monte Carlo (DIMC) method for modeling the radiative transfer equation from a gray treatment to a frequency-dependent one. The classic implicit Monte Carlo (IMC) algorithm, which has been used for several decades, suffers from a well-known numerical problem, called teleportation, where the photons might propagate faster than the exact solution due to the finite size of the spatial and temporal resolution. The semi-analog Monte Carlo algorithm proposed the use of two kinds of particles, photons and material particles, that are born when a photon is absorbed. The material particle can “propagate” only by transforming into a photon due to black-body emissions. While this algorithm produces a teleportation-free result, its results are noisier compared to the IMC due to the discrete nature of the absorption-emission process.
In a previous work, Steinberg and Heizler [ApJS, Vol. 258, p. 14 (2022)] proposed a gray version of DIMC that makes use of two kinds of particles, and therefore has teleportation-free results, but also uses the continuous absorption algorithm of IMC, yielding smoother results. This work is a direct frequency-dependent (energy-dependent) generalization of the DIMC algorithm. We find in several one- and two-dimensional benchmarks that the new frequency-dependent DIMC algorithm yields teleportation-free results on one hand, and smooth results with an IMC-like noise level.