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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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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.”
Toshio Wakabayashi, Isao Minatsuki
Nuclear Science and Engineering | Volume 83 | Number 1 | January 1983 | Pages 50-62
Technical Paper | doi.org/10.13182/NSE83-A17988
Articles are hosted by Taylor and Francis Online.
The physical behavior of burnable poison fuel pins, containing 0.1, 0.5, and 1.0 wt% Gd2O3 in 1.5 wt% UO2 pellets, has been studied through the measurements of reactivity change, coolant void reactivity, local power distribution, and thermal neutron flux distribution including fine structure, using a heavy-water-moderated, cluster-type fuel lattice. A new technique for utilizing a burnable poison has been developed using a gadolinium absorber rod inserted into the center of the cluster-type fuel assembly. Its physical behavior has been studied through the measurements of accompanying reactivity change, coolant void reactivity, local power distribution, and thermal neutron flux distribution. When the Gd2O3 content of the fuel pellets is more than 0.5 wt%, the reactivity effect is reduced largely due to the saturation of the thermal neutron self-shielding effect in the poisoned fuel pin. A gadolinium absorber rod inserted in the center of the fuel assembly, although it causes a small increase in local power peaking, is effective in the control of the initial excess reactivity and favorably affects the coolant void reactivity. An accurate calculation by the WIMS-D code requires division of the fuel pellet region into more than five mesh intervals owing to the enhancement of the thermal neutron self-shielding effect due to absorption by the gadolinium in the poisoned fuel pins.
