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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. L. Walsh
Nuclear Science and Engineering | Volume 102 | Number 2 | June 1989 | Pages 119-133
Technical Paper | doi.org/10.13182/NSE89-A23637
Articles are hosted by Taylor and Francis Online.
Calculations of fission neutron spectra and fission spectrum integrals for six fissioning systems are reported. The systems studied are thermal-neutron-induced fission of 233U, 235U, and 239Pu; 2-MeV neutron fission of 232Th and 238U; and spontaneous fission of 252Cf The Madland-Nix formalism is used, but is extended to take account of the spin of the fission fragment. Also, more recent values for the average energy release in fission are used. The results of the fission neutron spectrum calculations are given in tabular and graphical form for applied purposes and are compared with experimental data. Similar deviations from a Maxwellian spectrum are seen for each system. The effect on the fission neutron spectra of 233U, 235U, and 239Pu from inclusion of alternative values for the average total fragment kinetic energy is shown.
