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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
R. H. Karcher
Nuclear Science and Engineering | Volume 27 | Number 2 | February 1967 | Pages 367-387
Technical Paper | doi.org/10.13182/NSE67-A18276
Articles are hosted by Taylor and Francis Online.
The transport of neutrons from a point source of simulated weapons radiation in infinite air is calculated. Weapons neutron spectra are simulated using a mixed source composed of a chopped fission spectrum with most of the neutrons below 0.4 MeV deleted, and an equivalent number distributed uniformly in the 12- to 16-MeV range. The results obtained are generally conservative, from a shielding standpoint, for most nuclear devices. The method of track length stretching is used to improve the efficiency of the Monte Carlo analysis for deep penetration calculations. Well-converged fast-neutron flux and dose data are obtained for penetration distances of about 400 g/cm2 (approximately 2 miles in sea-level air at 68°F). Energy spectra and angular distributions are calculated also; however, the convergence is less satisfactory in this case. It is found that the inelastic and capture gamma sources resulting from neutron interaction in air are of extremely low intensity and are probably negligible for most shielding applications. Integral and differential neutron air-transport data are tabulated as a function of penetration distance to facilitate their use in shielding calculations.