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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.
A. N. Verma, Balesh Verma, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 72 | Number 2 | November 1979 | Pages 160-174
Technical Paper | doi.org/10.13182/NSE79-A19461
Articles are hosted by Taylor and Francis Online.
To study the anisotropy in scattering of thermal neutrons in beryllium, we have calculated elastic as well as inelastic differential cross sections. Anisotropy in elastic scattering is studied by replacing the δ function by a Gaussian function of suitable width. To study the anisotropy in inelastic scattering, we have calculated one-phonon coherent inelastic differential cross sections. The differential cross sections for the one- and two-phonon processes have also been calculated in the incoherent approximation. We have also expanded the angle dependence of cross section in terms of the Legendre polynomials. Using the above differential cross sections, the intensity of scattered neutrons in various angular directions has been calculated, and the results have been compared with the corresponding observed results of Aizawa et al. Calculated results are found in good agreement with the corresponding observed results. We have investigated the effect of anisotropy in scattering on steady-state angular spectra inside small beryllium assemblies. The calculated results have been compared with the observed results of Lake and Kallfelz and also with those obtained in the isotropic scattering approximation of Garg et al. It is found that the calculated spectra in the first angular direction (θ1 ≃ 28 deg) at various distances from the source plane are in better agreement with the corresponding observed results in the entire energy range than those obtained in the isotropic scattering approximation.
