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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
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.