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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.
J. W. Boldeman, J. Fréhaut, R. L. Walsh
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 430-436
Technical Paper | doi.org/10.13182/NSE77-A27060
Articles are hosted by Taylor and Francis Online.
Corrections of the large liquid scintillator measurements by Boldeman et al. and Soleilhac et al. for the delayed gamma rays from fission have produced consistent values for the average number of prompt neutrons () produced in the fission of 235U. The absolute value of for thermal-neutron fission is 2.389 ± 0.009, and the energy dependence is approximately linear. The data do not support the existence of fine structure between 200 and 600 keV nor the broad step-like structural dependence found in recent evaluations. However, there is the suggestion of a slight flattening of the curve representing the data between 250 and 600 keV.
