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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.
Tsuyoshi Misawa, Seiji Shiroya, Keiji Kanda
Nuclear Technology | Volume 116 | Number 1 | October 1996 | Pages 9-18
Technical Paper | Fission Reactor | doi.org/10.13182/NT96-A35308
Articles are hosted by Taylor and Francis Online.
Experiments on the reactivity worth of beryllium metal were performed using the Kyoto University Critical Assembly, and they were analyzed to examine the validity of the computational method to treat (n,2n) reactions in calculations. The experimental results demonstrated that beryllium metal has positive reactivity worth compared with graphite. In the analysis, (n,2n) reactions were treated as modifying scattering cross sections in a transport calculation, whereas both scattering and absorption cross sections should be modified in a diffusion calculation. The results of calculations for the reactivity worth of beryllium agreed with experimental data within a few percent in the calculated-to-experimental ratio. Calculated results indicated that (n,2n) reactions of beryllium contribute by ∼85% to the positive reactivity worth compared with graphite in these experiments at a thermal reactor. Moreover, through the improved neutron and gamma-ray coupled calculation, the effect of (γ,n) reactions of beryllium on reactivity was estimated. It was found that (γ,n) reactions of beryllium can be negligible so far as this reactivity worth is concerned.