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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
Janet Seltzer, W. K. Firk
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 415-419
Technical Paper | doi.org/10.13182/NSE74-A23372
Articles are hosted by Taylor and Francis Online.
The total neutron cross section of sodium has been measured in the vicinity of the 2.8-keV resonance with the high-resolution time-of-flight spectrometer associated with the Yale University 70-MeV Electron Linear Accelerator. The spin of the resonance is unambiguously identified to be J = 1 . A least-squares analysis of the cross section has been carried out up to an energy of 50 keV using a model that takes into account the effects of local and distant levels. The observed total cross section is well described throughout the entire range with a spin-independent interaction radius of 5.8 fm and with reasonable values of the R functions (distant level effects) for both spin states. The resonance energy, the neutron width, and the effective nuclear radii derived from the analysis are, respectively, ER = 2805 ± 30 eV, ΓnR = 376 ± 15 eV, aJ =1 = 5.3 fm, and aJ=2(E) = 5.7 + [2 × 108/(E + 18500)2] fm.
