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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.”
Ricardo Diniz, Adimir dos Santos
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 125-141
Technical Paper | doi.org/10.13182/NSE04-69
Articles are hosted by Taylor and Francis Online.
A reactor noise approach has been successfully performed at the IPEN/MB-01 research reactor facility to determine experimentally the effective delayed neutron parameters i and i in a six-group model. The method can be considered a novel one because it exploits the very low-frequency domain of the spectral densities. The proposed method has some advantages to other in-pile methods since it does not perturb the reactor system and consequently does not "excite" any sort of harmonic modes. As a by-product and a consistency check, the eff parameter was obtained without the need of the Diven factor and power normalization, and it is in excellent agreement with independent measurements. The theory/experiment comparison shows that for the abundances the JENDL3.3 presents the best performance, while for the decay constants the revised version of ENDF/B-VI.8 shows the best agreement. The best performance for the eff determination is obtained with JENDL3.3. In contrast, ENDF/B-VI.8 and its revised version performed at Los Alamos National Laboratory overestimate eff by as much as 4%. The eff results of this work totally support the proposal by Sakurai and Okajima to reduce the thermal delayed neutron yield of 235U.
