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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. Devooght
Nuclear Science and Engineering | Volume 67 | Number 2 | August 1978 | Pages 147-161
Technical Paper | doi.org/10.13182/NSE78-A15432
Articles are hosted by Taylor and Francis Online.
The spectrum of the multigroup-multipoint operator with delayed neutrons is studied under the assumption of a common fission spectrum. Using the fact that the fission operator is proportional to a projector, the Weinstein-Aronszajn technique for degenerate perturbation can be used. The general problem is first reduced to a problem without delayed neutrons. The high degeneracy of the spectrum is further examined and connected with the definition of “clusters.”