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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
José Canosa, Harvey Brooks
Nuclear Science and Engineering | Volume 26 | Number 2 | October 1966 | Pages 237-253
Technical Paper | doi.org/10.13182/NSE66-A28166
Articles are hosted by Taylor and Francis Online.
The xenon-induced oscillations in the power level (fundamental mode) and in the power distribution (first harmonic) have been studied for a slab reactor with prompt power reactivity feedback. One-group space-dependent kinetics equations and linearized theory are used throughout. The linear analysis rigorously predicts the onset of xenon oscillations; however, it does not say anything on how much the oscillation amplitude grows or decays. Explicit formulas giving the effects of the coupling of the infinite number of reactor modes with the fundamental mode and first harmonic are obtained and used for the first time to explain mode-coupling effects both qualitatively and quantitatively. Mode-coupling effects are quite small at the thermal flux levels of present power reactors [1013−1014 n/(cm2sec)]. At higher fluxes [1015 n/(cm2sec)] mode coupling is destabilizing and might be significant; here the negative feedback reactivity needed to provide stability must be increased by ≈ 10%, relative to the value obtained from a calculation where coupling is neglected. A study has been made on the influence of the equilibrium power distribution on both types of oscillations; this study gives information concerning the effects of a reflector on reactor kinetics. A new result is that, depending on flux level, a reflected reactor may be more stable than a bare reactor against fundamental mode oscillations.
