ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
May 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
June 2026
Nuclear Technology
Fusion Science and Technology
Latest News
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.
Y. D. Harker, R. A. Anderl, G. K. Becker, L. G. Miller
Nuclear Science and Engineering | Volume 110 | Number 4 | April 1992 | Pages 355-368
Technical Paper | doi.org/10.13182/NSE92-A23909
Articles are hosted by Taylor and Francis Online.
Neutron spectrum measurements are performed on the aluminum-oxide-filtered neutron beam at the Brookhaven Medical Research Reactor (BMRR). Two independent measurement techniques are used in the spectrum characterization: (a) foil activation spectrometry and (b) proton-recoil spectrometry. Activation foil assemblies are irradiated at the exit port of the beam facility. Dominant resonances in selected activation reactions are used to measure the epithermal neutron spectrum. The intermediate and fast energy ranges of the neutron spectrum are measured by threshold reactions and the 10B-filtered 235U fission reaction. Neutron spectral data are derived from the activation data by two approaches: (a) an analysis that yields neutron flux values at the energies of the dominant or primary resonances in the epithermal activation reactions and (b) an analysis that utilizes all the activation data simultaneously in a spectrum unfolding process using the FERRET data adjustment code. Hydrogen-filled proton-recoil proportional chambers are used at the beam port exit to acquire data of a higher energy resolution than that obtainable through foil activation techniques. These measurements are made to determine if structure in the aluminum scattering cross section would produce significant structure in the filtered spectrum in the fast neutron region.