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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. G. Alsmiller, Jr., T. A. Gabriel, M. P. Guthrie
Nuclear Science and Engineering | Volume 40 | Number 3 | June 1970 | Pages 365-374
Technical Paper | doi.org/10.13182/NSE70-A20187
Articles are hosted by Taylor and Francis Online.
Electron-photon cascade calculations and photoneutron-production calculations have been carried out for 150-MeV electrons on thick targets of Be and Ta. In the energy region of the giant resonance an evaporation model was used to calculate the production spectrum, and at higher energies (25 MeV) an intranuclear-cascade model was used. The calculated photoneutron-production spectra cover the energy range 0.01 to ∼100 MeV and are given for target thicknesses of 1 and 20 radiation lengths in both Ta and Be. A method is described and sufficient information is given so that estimates of the photoneutron-production spectra in targets of intermediate thicknesses may be obtained. Results on the photoproton-production spectra are also given. The spectra from the Ta and Be targets are compared and are found to have very different characteristics in that the number of low-energy (< 1 MeV) neutrons produced in the Ta target is much greater than that produced in the Be target and the number of high-energy ( a few MeV) neutrons produced in the Be target is larger than that produced in the Ta target.