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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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
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.
Bernard I. Spinrad, James S. Sterbentz
Nuclear Science and Engineering | Volume 90 | Number 4 | August 1985 | Pages 431-441
Technical Paper | doi.org/10.13182/NSE85-A18491
Articles are hosted by Taylor and Francis Online.
The Wigner-Seitz cell problem is treated by integral transport theory as a superposition of black boundary problems using the volume source and sources equivalent to the two lowest order angular components of the reentrant flux. This treatment sheds light on the convergence properties of iterative integral transport solution methods. The outgoing flux is required to have the lowest order components equal and opposite to those of the reentrant flux. Sample problems with this P11 boundary condition give good results. A new approximation to neutron transport theory is also reported. This approximation does not rely on expansion or approximation of the angular flux distribution, but rather on approximating the integral transport kernel by a sum of diffusionlike kernels that preserve spatial moments of the kernel. This might permit transport problems to be treated as a set of coupled diffusion problems in any geometry.