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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. Gwin, L. W. Weston, G. de Saussure, R. W. Ingle, J. H. Todd, F. E. Gillespie, R. W. Hockenbury, R. C. Block
Nuclear Science and Engineering | Volume 45 | Number 1 | July 1971 | Pages 25-36
Technical Paper | doi.org/10.13182/NSE71-A20342
Articles are hosted by Taylor and Francis Online.
The neutron absorption and fission cross sections for 239Pu have been measured simultaneously over the neutron energy range from 0.02 eV to 30 keV. These cross sections were measured using an ionization chamber containing 239Pu. The differential cross sections derived from these measurements are presented along with a multilevel analysis of the data up to 100 eV. A reevaluation of data obtained using a metal foil of 239Pu has also been made. Average values of the neutron capture and fission cross sections are presented for 239Pu as obtained using the ionization chamber as well as with the metal foil. A detailed comparison of the present data is made with the results of the ENDF/B evaluation for 239Pu (material 1104). The neutron cross sections presented in this report supersede the results reported previously by the authors of this report.
