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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.
N. Koyumdjieva, N. Janeva, K. Volev
Nuclear Science and Engineering | Volume 137 | Number 2 | February 2001 | Pages 194-205
Technical Paper | doi.org/10.13182/NSE01-A2185
Articles are hosted by Taylor and Francis Online.
There is a significant extension of the region of resolved resonances (RRR) for some nuclei to higher energies, and this has repercussions on the last updated versions of the evaluated nuclear data libraries. This energy extension covers intervals of the resonant cross-section structure, previously treated as an unresolved resonance region (URR). The reality of this situation provides an opportunity to verify a new statistical model of the resonant cross-section structure in the URR based on the characteristic function F of the R-matrix element distribution. For this purpose, the average cross sections and self-shielding factors obtained by the characteristic function model are compared with the corresponding quantities calculated by the Reich-Moore formalism of the R-matrix theory of nuclear reactions with the evaluated resonance parameters in the RRR. The ENDF/B-VI and JENDL 3.2 resolved resonance parameters of 56Fe and 238U are used for the cross-section calculations.
