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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.
K. Wisshak, F. Käppeler
Nuclear Science and Engineering | Volume 77 | Number 1 | January 1981 | Pages 58-70
Technical Paper | doi.org/10.13182/NSE81-A21339
Articles are hosted by Taylor and Francis Online.
The neutron capture width of the 27.7-keV s-wave resonance in 56Fe has been determined using a setup completely different from most of the previous experiments. A pulsed 3-MV Van de Graaff accelerator and the 7Li(p,n) reaction served as a neutron source. Capture gamma rays were observed by a Moxon-Rae detector and gold was used as a standard. The samples were positioned at a flight path of only 7.6 to 8.0 cm. This allowed the use of very thin samples avoiding large multiple scattering corrections. Three metallic disks enriched in 56Fe were used with a thickness between 0.6 and 0.15 mm. Events due to capture of resonance scattered neutrons in the detector or surrounding material were completely eliminated by time-of-flight. The result for the capture width is Γγ = 1.01 eV with a statistical uncertainty of 1.3% and a systematic uncertainty of ∼5%.