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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, J. A. Mitchell, N. M. Steen
Nuclear Science and Engineering | Volume 52 | Number 3 | November 1973 | Pages 406-412
Technical Note | doi.org/10.13182/NSE73-A19488
Articles are hosted by Taylor and Francis Online.
The 233U fission neutron spectrum has been measured by pulsed-beam time-of-flight techniques from 0.8 to 10 MeV. Above ≈2 MeV, the data were found, within statistics, to be adequately represented by either the model in the ENDF/B-III file or a best fit Maxwellian distribution with nearly the same average energy. At lower energy, the data appear to follow the ENDF/B representation somewhat more closely. The fit of a Maxwellian distribution to the 233U data yielded an average “temperature” parameter of 1.34 ± 0.02 MeV, where the error includes both statistical and systematic uncertainties. A similar fit to data taken for a 235U sample yielded a temperature parameter of 1.31 ± 0.03 MeV; however, the best estimated difference in temperature is 16 ± 6 keV.
