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Division Spotlight
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.”
Nathan E. White, Sudarshan K. Loyalka
Nuclear Science and Engineering | Volume 181 | Number 3 | November 2015 | Pages 318-330
Technical Paper | doi.org/10.13182/NSE15-10
Articles are hosted by Taylor and Francis Online.
In high-temperature gas-cooled reactors (HTGRs), carbonaceous dust can be generated both during normal operations and during accidents. The dust particles can be highly irregular and highly porous and have very large surface areas that may make dust-facilitated (or dust-hindered) fission product (FP) transport a major factor. Since the FP interactions with dust can occur while the dust is on a surface as well as in suspension, there is a need to obtain computational and experimental results for both situations. In 2014, Smith and Loyalka used the Green's Function Method to study condensation (results for absorption/deposition and evaporation are generally directly related to the condensation problem) on chainlike particles and particle agglomerates in the diffusion regime. In 2010, Smith and Loyalka made progress in computation of evaporation/condensation particles on a surface, but again in the diffusion regime. Since the particle sizes of interest span a wide range—from nanometers to microns (10−9 m to 10−6 m)—and are also porous with small pores and pathways for FPs, these computations need to be extended to the transport regime where the particle sizes (and/or pores) are comparable to the vapor (FP) molecular mean free path (∼0.05 μm) in the gaseous phase (air or helium, or some mix thereof with other contaminants). The focus of the present paper is on Monte Carlo computation of condensation rate on chainlike particles and particle agglomerates in the transport regime using the one-speed approximation, and we report a number of new results that provide new insights and path for future explorations.