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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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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Michael F. Roche, Leonard Leibowitz, Jack L. Settle, Carl E. Johnson, Richard C. Vogel, Robert L. Ritzman
Nuclear Technology | Volume 96 | Number 1 | October 1991 | Pages 96-116
Technical Paper | Material | doi.org/10.13182/NT91-A35536
Articles are hosted by Taylor and Francis Online.
The vaporization of strontium, barium, and lanthanum from mixtures of their oxides with urania, zir-conia, and concrete is determined with the objective of understanding the release of these refractory fission products during the core/concrete interaction phase of a degraded core accident. The vaporization of uranium and the total mass vaporized are also determined. Three different concretes having silica contents ranging from 7 to 69 wt% are used to reflect the known range of reactor basemat compositions. In the experiments, the mixtures are vaporized at 2150 or 2400 K into flowing H2 or He-6 H2 gas. The total mass of material that was vaporized is determined by weighing the condensates; the masses of individual elements are determined by chemical analyses of the condensates. The phases present in the heated mixtures are inferred from electron probe microanalyses and X-ray diffraction analyses. Equilibrium calculations are performed using SOLGASMIX and a thermodynamic data base containing 112 gaseous and 108 condensed species. The partial molar free energy of oxygen is calculated from the equilibrium oxygen pressure established in the high-temperature reaction zone between the gas and the sample. Using this experimental data, the release to be expected in the molten core/concrete interaction phase of a severe nuclear reactor accident is estimated. The estimated release of strontium, barium, lanthanum, and uranium is <1% with a basemat concrete of low silica content (7 wt%) and decreases to <0.01% with a basemat concrete of high silica content (69 wt%). The estimated total mass release is ∼0.5% with all three concrete types.