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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.
Gilberto Espinosa-Paredes, Marco Antonio Polo-Labarrios
Nuclear Science and Engineering | Volume 171 | Number 3 | July 2012 | Pages 258-264
Technical Note | doi.org/10.13182/NSE11-58
Articles are hosted by Taylor and Francis Online.
In this technical note we develop a new approximation from the solution of the time-dependent Boltzmann equation, which includes a fractional constitutive equation of the neutron current density, for a general medium. The fractional constitutive equation in combination with the conservation law that governs the particle collision and reaction processes (P1) approximation for the transport equation gives a time-fractional telegrapher's equation (TFTE). The wave velocity found with this approximation is 3-/2 for < 1. The numerical results are compared with the exact solution and Heizler's approximation. We found that the TFTE gives the best estimate for a purely absorbing medium, where most approximations fail. The asymptotic diffusion coefficient was applied for a heterogeneous medium, and the results show that the behavior of the TFTE improves.
