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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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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.”
L. Erradi, A. Santamarina, O. Litaize
Nuclear Science and Engineering | Volume 144 | Number 1 | May 2003 | Pages 47-73
Technical Paper | doi.org/10.13182/NSE144-47
Articles are hosted by Taylor and Francis Online.
The contributions of different physical phenomena to the reactivity temperature coefficient (RTC) in typical light water moderated lattices have been assessed. Using the APOLLO2 code with the CEA93 cross-section library based on JEF2.2 data, we have analyzed the main French experiments available on the RTC: the CREOLE and MISTRAL experiments. In these experiments performed in the EOLE critical facility located at CEA/Cadarache, the RTC has been measured in both UO2 and UO2-PuO2 pressurized water reactor-type lattices. Our calculations have shown that the calculation error in UO2 lattices is <1 pcm/°C, which is considered as the target accuracy for reactor design calculations. On the other hand the calculation error in mixed oxide lattices is more significant in both low- and high-temperature ranges: An average error of -2 ± 0.5 pcm/°C is observed at low temperatures, and an error of +3 ± 2 pcm/°C is obtained for temperatures >250°C. Our analysis has shown that the negative error in the low-temperature range is linked to the thermal spectrum shift effect, which is strongly dependent on the thermal shapes of the cross sections of plutonium isotopes, whereas the positive error in the high-temperature range is mainly linked to the water density effects.
