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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.
R. E. Maerker, F. J. Muckenthaler
Nuclear Science and Engineering | Volume 42 | Number 3 | December 1970 | Pages 335-351
Technical Paper | doi.org/10.13182/NSE70-A21222
Articles are hosted by Taylor and Francis Online.
Measurements have been made at the Tower Shielding Facility of the spectra of secondary gamma rays arising from fast-neutron interactions in samples of natural iron, aluminum, copper, zinc, titanium, potassium, calcium, sodium, silicon, nickel, barium, sulfur, and a type-321 stainless steel. The absolute spectra are expressed as values of (Δ Eγ) = 4π d/dΩ (ΔEγ, 90 deg), where (ΔEγ) is the production cross section in millibarns averaged over an incident neutron spectrum from 1 to 14 MeV for 0.5-MeV wide gamma-ray intervals lying between approximately 1 and 6.5 MeV in gamma-ray energy. These data are intended primarily as integral checks on existing and future production cross-section sets which are differential in both the gamma-ray and neutron energy. Agreement with existing sets of data is adequate for iron, nickel, chromium, calcium, and aluminum. The agreement is fair to poor for the remaining elements where comparisons could be made.