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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.
L. Green
Nuclear Science and Engineering | Volume 37 | Number 2 | August 1969 | Pages 232-242
Technical Paper | doi.org/10.13182/NSE69-A20683
Articles are hosted by Taylor and Francis Online.
The spontaneous fission neutron spectrum from 252Cf was measured using a variation of the transmission method. An excellent fit to the data was calculated assuming a Maxwellian spectrum shape with a temperature of 1.39 ± 0.04 MeV. The error includes contributions from uncertainties in cross sections and experimental statistics. In addition, all other possible sources of systematic error were investigated and found to be negligible. This value is in good agreement with earlier results at the low end of the range of measured values of the Maxwellian temperature.
